Significant Accounting Policies	12 Months Ended
Mar. 31, 2016
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Nature of Operations: McKesson Corporation (“McKesson,” the “Company,” the “Registrant” or “we” and other similar pronouns) delivers a comprehensive offering of pharmaceuticals and medical supplies and provides services to help our customers improve the efficiency and effectiveness of their healthcare operations. We manage our business through two operating segments, McKesson Distribution Solutions and McKesson Technology Solutions, as further described in Financial Note 27, “Segments of Business.” Basis of Presentation: The consolidated financial statements and accompanying notes are prepared in accordance with U. S. generally accepted accounting principles (“GAAP”). The consolidated financial statements of McKesson include the financial statements of all wholly-owned subsidiaries and majority-owned or controlled companies. For those consolidated subsidiaries where our ownership is less than 100%, the portion of the net income or loss allocable to the noncontrolling interests is reported as “Net Income Attributable to Noncontrolling Interests” on the consolidated statements of operations. All significant intercompany balances and transactions have been eliminated in consolidation. We consider ourselves to control an entity if we are the majority owner of and have voting control over such entity. We also assess control through means other than voting rights (“variable interest entities” or “VIEs”) and determine which business entity is the primary beneficiary of the VIE. We consolidate VIEs when it is determined that we are the primary beneficiary of the VIE. Investments in business entities in which we do not have control, but have the ability to exercise significant influence over operating and financial policies, are accounted for using the equity method and our proportionate share of income or loss is recorded in other income, net. Equity investments in non-publicly traded entities are primarily accounted for using the cost method. Intercompany transactions and balances have been eliminated. Fiscal Period: The Company’s fiscal year begins on April 1 and ends on March 31. Unless otherwise noted, all references to a particular year shall mean the Company’s fiscal year. Reclassifications: Certain prior year amounts have been reclassified to conform to the current year presentation. Use of Estimates: The preparation of financial statements in conformity with U.S. GAAP requires that we make estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying notes. Actual amounts could differ from those estimated amounts. Cash and Cash Equivalents: All highly liquid debt and money market instruments purchased with original maturity of three months or less at the date of acquisition are included in cash and cash equivalents. Cash equivalents, which are available-for-sale, are carried at fair value. Cash equivalents are primarily invested in AAA rated prime and U.S. government money market funds denominated in U.S. dollars, AAA rated prime money market funds denominated in Euros, overnight repurchase agreements collateralized by U.S. government securities, Canadian government securities and/or securities that are guaranteed or sponsored by the U.S. government and an AAA rated prime money market fund denominated in British pound sterling. The remaining cash and cash equivalents are deposited with several financial institutions. Deposits may exceed the amounts insured by the Federal Deposit Insurance Corporation in the U.S. and similar deposit insurance programs in other jurisdictions. We mitigate the risk of our short-term investment portfolio by depositing funds with reputable financial institutions and monitoring risk profiles and investment strategies of money market funds. Restricted Cash: Cash that is subject to legal restrictions or is unavailable for general operating purposes is classified as restricted cash and is included within “Prepaid expenses and other” and “Other Noncurrent Assets” in the consolidated balance sheets. At March 31, 2016, our restricted cash balance was $939 million, which represents cash paid into the escrow accounts for acquisitions that closed on April 1, 2016. There was no material restricted cash balance at March 31, 2015. Marketable Securities Available-for-Sale: We carry our marketable securities, which are available-for-sale, at fair value and they are included in prepaid expenses and other in the consolidated balance sheets. The unrealized gains and losses, net of the related tax effect, computed in marking these securities to market have been reported within stockholders’ equity. At March 31, 2016 and 2015, marketable securities were not material. In determining whether an other-than-temporary decline in market value has occurred, we consider the duration that, and extent to which, the fair value of the investment is below its cost, the financial condition and future prospects of the issuer or underlying collateral of a security, and our intent and ability to retain the security in order to allow for an anticipated recovery in fair value. Other-than-temporary declines in fair value from amortized cost for available-for-sale equity securities that we intend to sell or would more likely than not be required to sell before the expected recovery of the amortized cost basis are charged to other income, net, in the period in which the loss occurs. Concentrations of Credit Risk and Receivables: Our trade receivables are subject to a concentration of credit risk with customers primarily in our Distribution Solutions segment. During 2016, sales to our ten largest customers, including group purchasing organizations (“GPOs”) accounted for approximately 52.4% of our total consolidated revenues. Sales to our largest customer, CVS Health (“CVS”), accounted for approximately 20.3% of our total consolidated revenues. At March 31, 2016, trade accounts receivable from our ten largest customers were approximately 32% of total trade accounts receivable. Accounts receivable from CVS were approximately 18% of total trade accounts receivable. As a result, our sales and credit concentration is significant. We also have agreements with GPOs, each of which functions as a purchasing agent on behalf of member hospitals, pharmacies and other healthcare providers, as well as with government entities and agencies. The accounts receivables balances are with individual members of the GPOs, and therefore no significant concentration of credit risk exists. A default in payment, a material reduction in purchases from these or any other large customers, or the loss of a large customer or customer groups could have a material adverse impact on our financial condition, results of operations and liquidity. In addition, trade receivables are subject to a concentration of credit risk with customers in the institutional, retail and healthcare provider sectors, which can be affected by a downturn in the economy and changes in reimbursement policies. This credit risk is mitigated by the size and diversity of the customer base as well as its geographic dispersion. We estimate the receivables for which we do not expect full collection based on historical collection rates and ongoing evaluations of the creditworthiness of our customers. An allowance is recorded in our consolidated financial statements for these amounts. Financing Receivables: We assess and monitor credit risk associated with financing receivables, namely lease and notes receivables, through regular review of our collection experience in determining our allowance for loan losses. On an ongoing basis, we also evaluate credit quality of our financing receivables utilizing aging of receivables and write-offs, as well as considering existing economic conditions, to determine if an allowance is necessary. Financing receivables are derecognized if legal title to them has been transferred and all related risks and rewards incidental to ownership have passed to the buyer. As of March 31, 2016 and 2015, financing receivables and the related allowance were not material to our consolidated financial statements. Inventories: We report inventories at the lower of cost or market (“LCM”). Inventories for our Distribution Solutions segment consist of merchandise held for resale. For our Distribution Solutions segment, the majority of the cost of domestic inventories is determined using the last-in, first-out (“LIFO”) method. The majority of the cost of inventories held in foreign locations is based on weighted average purchase prices using the first-in, first-out method (“FIFO”). Technology Solutions segment inventories consist of computer hardware with cost generally determined by the standard cost method, which approximates average cost. Rebates, cash discounts, and other incentives received from vendors are recognized within cost of sales upon the sale of the related inventory. The LIFO method was used to value approximately 74% and 73% of our inventories at March 31, 2016 and 2015. If we had used the FIFO method of inventory valuation, which approximates current replacement costs, inventories would have been approximately $1,012 million and $768 million higher than the amounts reported at March 31, 2016 and 2015, respectively. These amounts are equivalent to our LIFO reserves. Our LIFO valuation amount includes both pharmaceutical and non-pharmaceutical products. In 2016, 2015 and 2014, we recognized LIFO related expenses of $244 million, $337 million and $311 million in cost of sales within our consolidated statements of operations. A LIFO expense is recognized when the net effect of price increases on pharmaceutical and non-pharmaceutical products held in inventory exceeds the impact of price declines, including the effect of branded pharmaceutical products that have lost market exclusivity. A LIFO credit is recognized when the net effect of price declines exceeds the impact of price increases on pharmaceutical and non-pharmaceutical products held in inventory. We believe that the average inventory costing method provides a reasonable estimation of the current cost of replacing inventory (i.e., “market”). As such, our LIFO inventory is valued at the lower of LIFO or market. Due to cumulative net price deflation from 2005 to 2013, we had a lower-of-cost or market (“LCM”) reserve of $60 million at March 31, 2013 which reduced pharmaceutical inventories at LIFO to market. During 2014, the LCM reserve of $60 million was released, resulting in an increase in gross profit. As of March 31, 2016 and 2015, inventories at LIFO did not exceed market. Shipping and Handling Costs: We include costs to pack and deliver inventory to our customers in selling, distribution and administrative expenses. Shipping and handling costs of $789 million, $819 million, $535 million were included in our selling, distribution and administrative expenses in 2016, 2015 and 2014. Property, Plant and Equipment: We state our property, plant and equipment (“PPE”) at cost and depreciate them under the straight-line method at rates designed to distribute the cost of PPE over estimated service lives ranging from one to thirty years. When certain events or changes in operating conditions occur, an impairment assessment may be performed on the recoverability of the carrying amounts. Goodwill: Goodwill is tested for impairment on an annual basis in the fourth quarter or more frequently if indicators for potential impairment exist. Impairment testing is conducted at the reporting unit level, which is generally defined as a component, one level below our Distribution Solutions and Technology Solutions operating segments, for which discrete financial information is available and segment management regularly reviews the operating results of that unit. The first step in goodwill testing requires us to compare the estimated fair value of a reporting unit to its carrying value. This step may be performed utilizing either a qualitative or quantitative assessment. If the carrying value of the reporting unit is lower than its estimated fair value, no further evaluation is necessary. If the carrying value of the reporting unit is higher than its estimated fair value, the second step must be performed to measure the amount of impairment loss. Under the second step, the implied fair value of goodwill is calculated in a hypothetical analysis by subtracting the fair value of all assets and liabilities of the reporting unit, including any unrecognized intangible assets, from the fair value of the reporting unit calculated in the first step of the impairment test. If the carrying value of goodwill for the reporting unit exceeds the implied fair value of goodwill, an impairment charge is recorded for that excess. To estimate the fair value of our reporting units, we use a combination of the market approach and the income approach. Under the market approach, we estimate fair value by comparing the business to similar businesses or guideline companies whose securities are actively traded in public markets. Under the income approach, we use a discounted cash flow model in which cash flows anticipated over several periods, plus a terminal value at the end of that time horizon, are discounted to their present value using an appropriate expected rate of return. The discount rate used for cash flows reflects capital market conditions and the specific risks associated with the business. In addition, we compare the aggregate of the reporting units’ fair value to the Company’s market capitalization as a further corroboration of the fair values. The testing requires a complex series of assumptions and judgment by management in projecting future operating results, selecting guideline companies for comparisons and assessing risks. The use of alternative assumptions and estimates could affect the fair values and change the impairment determinations. Intangible Assets: Currently all of our intangible assets are subject to amortization and are amortized based on the pattern of their economic consumption or on a straight-line basis over their estimated useful lives, ranging from one to thirty-eight years. We review intangible assets for impairment whenever events or changes in circumstances indicate that the carrying value of the assets may not be recoverable. Determination of recoverability is based on the lowest level of identifiable estimated future undiscounted cash flows resulting from use of the asset and its eventual disposition. Measurement of any impairment loss is based on the excess of the carrying value of the asset over its fair market value. Capitalized Software Held for Sale: Development costs for software held for sale, which primarily pertain to our Technology Solutions segment, are capitalized once a project has reached the point of technological feasibility. Completed projects are amortized after reaching the point of general availability using the straight-line method based on an estimated useful life of approximately three years. At each balance sheet date, or earlier if an indicator of an impairment exists, we evaluate the recoverability of unamortized capitalized software costs based on estimated future undiscounted revenues net of estimated related costs over the remaining amortization period. Capitalized Software Held for Internal Use: We capitalize costs of software held for internal use during the application development stage of a project and amortize those costs over their estimated useful lives ranging from one to ten years. As of March 31, 2016 and 2015, capitalized software held for internal use was $435 million, net of accumulated amortization of $1,130 million and $1,112 million, and was included in other assets in the consolidated balance sheets. Insurance Programs: Under our insurance programs, we seek to obtain coverage for catastrophic exposures as well as those risks required to be insured by law or contract. It is our policy to retain a significant portion of certain losses primarily related to workers’ compensation and comprehensive general, product and vehicle liability. Provisions for losses expected under these programs are recorded based upon our estimate of the aggregate liability for claims incurred as well as for claims incurred but not yet reported. Such estimates utilize certain actuarial assumptions followed in the insurance industry. Revenue Recognition: Distribution Solutions Revenues for our Distribution Solutions segment are recognized when persuasive evidence of an arrangement exists, product is delivered and title passes to the customer or when services have been rendered and there are no further obligations to the customer, the price is fixed or determinable, and collection of the amounts are reasonably assured. Revenues for our Distribution Solutions segment include large volume sales of pharmaceuticals primarily to a limited number of large customers who warehouse their own products. We order bulk product from the manufacturer, receive and process the product primarily through our central distribution facility and deliver the bulk product (generally in the same form as received from the manufacturer) directly to our customers’ warehouses. We also record revenues for direct store deliveries of shipments from the manufacturer to our customers. We assume the primary liability to the manufacturer for these products. Revenues are recorded gross when we are the primary party obligated in the transaction, take title to and possession of the inventory, are subject to inventory risk, have latitude in establishing prices, assume the risk of loss for collection from customers as well as delivery or return of the product, are responsible for fulfillment and other customer service requirements, or the transactions have several but not all of these indicators. Revenues are recorded net of sales returns, allowances, rebates and other incentives. Our sales return policy generally allows customers to return products only if they can be resold for value or returned to suppliers for credit. Sales returns are accrued based on estimates at the time of sale to the customer. Sales returns from customers were approximately $3.1 billion in 2016, $2.7 billion in 2015 and $1.9 billion in 2014. Taxes collected from customers and remitted to governmental authorities are presented on a net basis; that is, they are excluded from revenues. Our Distribution Solutions segment also engages in multiple-element arrangements, which may contain a combination of various products and services. Revenue from a multiple-element arrangement is allocated to the separate elements based on their relative selling price and recognized in accordance with the revenue recognition criteria applicable to each element. Relative selling price is determined based on vendor-specific objective evidence (“VSOE”) of selling price, if available, third-party evidence (“TPE”), if VSOE of selling price is not available, or estimated selling price (“ESP”), if neither VSOE of selling price nor TPE is available. Technology Solutions Revenues for our Technology Solutions segment are generated primarily by licensing software and software systems (consisting of software, hardware and maintenance support), providing software as a service (“Saas”) or SaaS-based solutions and providing claims processing, outsourcing and professional services. Revenue for this segment is recognized as follows: Software systems are marketed under information systems agreements as well as service agreements. Perpetual software arrangements are recognized at the time of delivery or under the percentage-of-completion method if the arrangements require significant production, modification or customization of the software. Contracts accounted for under the percentage-of-completion method are generally measured based on the ratio of labor hours incurred to date to total estimated labor hours to be incurred. Changes in estimates to complete and revisions in overall profit estimates on these contracts are charged to earnings in the period in which they are determined. We accrue for contract losses if and when the current estimate of total contract costs exceeds total contract revenue. Revenue from time-based software license agreements is recognized ratably over the term of the agreement. Software implementation fees are recognized as the work is performed or under the percentage-of-completion method. Maintenance and support agreements are marketed under annual or multi-year agreements and are recognized ratably over the period covered by the agreements. Hardware revenues are generally recognized upon delivery. SaaS-based subscription, content and transaction processing fees are generally marketed under annual and multi-year agreements and are recognized ratably over the contracted terms beginning on the service start date for fixed fee arrangements and recognized as transactions are performed beginning on the service start date for per-transaction fee arrangements. Remote processing service fees are recognized monthly as the service is performed. Outsourcing service revenues are recognized as the service is performed. We also offer certain products on an application service provider basis, making our software functionality available on a remote hosting basis from our data centers. The data centers provide system and administrative support, as well as hosting services. Revenue on products sold on an application service provider basis is recognized on a monthly basis over the term of the contract beginning on the service start date of products hosted. This segment engages in multiple-element arrangements, which may contain any combination of software, hardware, implementation, SaaS-based offerings, consulting services or maintenance services. For multiple-element arrangements that do not include software, revenue is allocated to the separate elements based on their relative selling price and recognized in accordance with the revenue recognition criteria applicable to each element. Relative selling price is determined based on VSOE of selling price if available, TPE, if VSOE of selling price is not available, or ESP if neither VSOE of selling price nor TPE is available. For multiple-element arrangements accounted for in accordance with specific software accounting guidance when some elements are delivered prior to others in an arrangement and VSOE of fair value exists for the undelivered elements, revenue for the delivered elements is recognized upon delivery of such items. The segment establishes VSOE for hardware and implementation and consulting services based on the price charged when sold separately, and for maintenance services, based on renewal rates offered to customers. Revenue for the software element is recognized under the residual method only when fair value has been established for all of the undelivered elements in an arrangement. If fair value cannot be established for any undelivered element, all of the arrangement’s revenue is deferred until the delivery of the last element or until the fair value of the undelivered element is determinable. For multiple-element arrangements with both software elements and nonsoftware elements, arrangement consideration is allocated between the software elements as a whole and nonsoftware elements. The segment then further allocates consideration to the individual elements within the software group, and revenue is recognized for all elements under the applicable accounting guidance and our policies described above. Supplier Incentives: Fees for service and other incentives received from suppliers, relating to the purchase or distribution of inventory, are generally reported as a reduction to cost of sales. We consider these fees and other incentives to represent product discounts and as a result, the amounts are recognized within cost of sales upon the sale of the related inventory. Supplier Reserves: We establish reserves against amounts due from suppliers relating to various fees for services and price and rebate incentives, including deductions taken against payments otherwise due to them. These reserve estimates are established based on judgment after considering the status of current outstanding claims, historical experience with the suppliers, the specific incentive programs and any other pertinent information available. We evaluate the amounts due from suppliers on a continual basis and adjust the reserve estimates when appropriate based on changes in factual circumstances. All adjustments to supplier reserves are included in cost of sales. The ultimate outcome of any outstanding claims may be different than our estimate. As of March 31, 2016 and 2015 supplier reserves were $144 million and $167 million. All of the supplier reserves at March 31, 2016 and 2015 pertain to our Distribution Solutions segment. Income Taxes: We account for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial statements and the tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Tax benefits from uncertain tax positions are recognized when it is more likely than not that the position will be sustained upon examination, including resolutions of any related appeals or litigation processes, based on the technical merits. The amount recognized is measured as the largest amount of tax benefit that is greater than 50 percent likely of being realized upon effective settlement. Deferred taxes are not provided on undistributed earnings of our foreign operations that are considered to be permanently reinvested. Foreign Currency Translation: The reporting currency of the Company and its subsidiaries is the U.S. dollar. Our foreign subsidiaries generally consider their local currency to be their functional currency. Foreign currency-denominated assets and liabilities of these foreign subsidiaries are translated into U.S. dollars at year-end exchange rates and revenues and expenses are translated at average exchange rates during the corresponding period, and stockholders’ equity accounts are primarily translated at historical exchange rates. Foreign currency translation adjustments are included in other comprehensive income or loss in the statements of consolidated comprehensive income, and the cumulative effect is included in the stockholders’ equity section of the consolidated balance sheets. Realized gains and losses from currency exchange transactions are recorded in operating expenses in the consolidated statements of operations and were not material to our consolidated results of operations in 2016, 2015 or 2014. We release cumulative translation adjustment from stockholders’ equity into net income as a gain or loss only upon complete or substantially complete liquidation of a controlling interest in a subsidiary or a group of assets within a foreign entity. We also release all or a pro rata portion of the cumulative translation adjustment into net income upon the sale of an equity method investment that is a foreign entity. Derivative Financial Instruments: Derivative financial instruments are used principally in the management of foreign currency exchange and interest rate exposures and are recorded on the consolidated balance sheets at fair value. If a derivative is designated as a fair value hedge, the changes in the fair value of the derivative and of the hedged item attributable to the hedged risk are recognized as a charge or credit to earnings. If the derivative is designated as a cash flow hedge, the effective portions of changes in the fair value of the derivative are included in other comprehensive income or loss in the statements of consolidated comprehensive income, and the cumulative effect is included in the stockholders’ equity section of the consolidated balance sheets. The cumulative changes in fair value are reclassified to the consolidated statements of operations when the hedged item affects earnings. We periodically evaluate hedge effectiveness, and ineffective portions of changes in the fair value of cash flow hedges are recognized as a charge or credit to earnings. Derivative instruments not designated as hedges are marked-to-market at the end of each accounting period with the change included in earnings. Comprehensive Income: Comprehensive income consists of two components, net income and other comprehensive income. Other comprehensive income refers to revenue, expenses, and gains and losses that under GAAP are recorded as an element of stockholders’ equity but are excluded from net income. Our other comprehensive income primarily consists of foreign currency translation adjustments from those subsidiaries where the local currency is the functional currency, unrealized gains and losses on cash flow hedges, as well as unrealized gains and losses on retirement-related benefit plans. Noncontrolling Interests and Redeemable Noncontrolling Interests: Noncontrolling interests represent the portion of profit or loss, net assets and comprehensive income that is not allocable to McKesson Corporation. In 2016 and 2015, net income attributable to noncontrolling interests primarily represents guaranteed dividends and recurring compensation that McKesson is obligated to pay to the noncontrolling shareholders of Celesio AG (“Celesio”). Noncontrolling interests with redemption features, such as put rights, that are not solely within the Company’s control are considered redeemable noncontrolling interests. Redeemable noncontrolling interests are presented outside of Stockholders’ Equity on our consolidated balance sheet. Refer to Financial Note 10, “Noncontrolling Interests and Redeemable Noncontrolling Interests,” for more information. Share-Based Compensation: We account for all share-based compensation transactions using a fair-value based measurement method. The share-based compensation expense, for the portion of the awards that is ultimately expected to vest, is recognized on a straight-line basis over the requisite service period. The compensation expense recognized has been classified in the consolidated statements of operations or capitalized on the consolidated balance sheets in the same manner as cash compensation paid to our employees. Loss Contingencies: We are subject to various claims, including claims with customers and vendors, pending and potential legal actions for damages, investigations relating to governmental laws and regulations and other matters arising out of the normal conduct of our business. When a loss is considered probable and reasonably estimable, we record a liability in the amount of our best estimate for the ultimate loss. However, the likelihood of a loss with respect to a particular contingency is often difficult to predict and determining a meaningful estimate of the loss or a range of loss may not be practicable based on the information available and the potential effect of future events and decisions by third parties that will determine the ultimate resolution of the contingency. Moreover, it is not uncommon for such matters to be resolved over many years, during which time relevant developments and new information must be reevaluated at least quarterly to determine both the likelihood of potential loss and whether it is possible to reasonably estimate a range of possible loss. When a material loss is probable but a reasonable estimate cannot be made, disclosure of the proceeding is provided. Disclosure is also provided when it is reasonably possible that a loss will be incurred or when it is reasonably possible that the amount of a loss will exceed the recorded provision. We review all contingencies at least quarterly to determine whether the likelihood of loss has changed and to assess whether a reasonable estimate of the loss or range of the loss can be made. As discussed above, development of a meaningful estimate of loss or a range of potential loss is complex when the outcome is directly dependent on negotiations with or decisions by third parties, such as regulatory agencies, the court system and other interested parties. Such factors bear directly on whether it is possible to reasonably estimate a range of potential loss and boundaries of high and low estimate. Business Combinations: We account for acquired businesses using the acquisition method of accounting, which requires that once control is obtained of a business, 100% of the assets acquired and liabilities assumed, including amounts attributed to noncontrolling interests, be recorded at the date of acquisition at their respective fair values. Any excess of the purchase price over the estimated fair values of the net assets acquired is recorded as goodwill. Acquisition-related expenses and related restructuring costs are expensed as incurred. Several valuation methods may be used to determine the fair value of assets acquired and liabilities assumed. For intangible assets, we typically use the income method. This method starts with a forecast of all of the expected future net cash flows for each asset. These cash flows are then adjusted to present value by applying an appropriate discount rate that reflects the risk factors associated with the cash flow streams. Some of the more significant estimates and assumptions inherent in the income method or other methods include the amount and timing of projected future cash flows, the discount rate selected to measure the risks inherent in the future cash flows and the assessment of the asset’s life cycle and the competitive trends impacting the asset, including consideration of any technical, legal, regulatory, or economic barriers to entry. Determining the useful life of an intangible asset also requires judgment as different types of intangible assets will have different useful lives and certain assets may even be considered to have indefinite useful lives. Recently Adopted Accounting Pronouncements Deferred Income Taxes: In November 2015, amended guidance was issued for the balance sheet classification of deferred income taxes. The amended guidance requires the classification of all deferred tax assets and liabilities as noncurrent on the balance sheet instead of separating deferred taxes into current and noncurrent amounts. The amended guidance would have been effective for us commencing in the first quarter of 2018, however, early adoption was permitted. We early adopted this amended guidance in the fourth quarter of 2016 on a prospective basis. As a result, we reclassified current net deferred tax liabilities of approximately $2 billion on our consolidated balance sheet as of March 31, 2016. Our March 31, 2015 balances were not retrospectively adjusted. The adoption of this guidance had no impact on our condensed consolidated statements of earnings, comprehensive income or cash flows. This amended guidance only resulted in a change in presentation of our deferred income taxes on our consolidated balance sheet as of March 31, 2016. Discontinued Operations: In the first quarter of 2016, we adopted amended guidance for reporting of discontinued operations and disclosures of disposals of components. The amended guidance revises the criteria for disposals to qualify as discontinued operations and permits significant continuing involvement and continuing cash flows with the discontinued operation. In addition, the amended guidance requires additional disclosures for discontinued operations and new disclosures for individually material disposal transactions that do not meet the definition of a discontinued operation. Refer to Financial Note 5, “Divestiture of Businesses,” for more information regarding the impact of this amended guidance on our consolidated financial statements. Cumulative Translation Adjustment: In the first quarter of 2015, we adopted amended guidance for a parent’s accounting for the cumulative translation adjustment upon derecognition of certain subsidiaries or group of assets within a foreign entity or of an investment in a foreign entity. The amended guidance requires the release of any cumulative translation adjustment into net income only upon complete or substantially complete liquidation of a controlling interest in a subsidiary or a group of assets within a foreign entity. Also, it requires the release of all or a pro rata portion of the cumulative translation adjustment to net income in the case of sale of an equity method investment that is a foreign entity. The adoption of this amended guidance did not have a material effect on our consolidated financial statements. Recently Issued Accounting Pronouncements Not Yet Adopted Share-Based Payments: In March 2016, amended guidance was issued for employee share-based payment awards. The amended guidance makes several modifications related to the accounting for forfeitures, employer tax withholding on share-based compensation and excess tax benefits or deficiencies. The amended guidance also clarifies the statement of cash flows presentation for share-based awards. The amended guidance is effective for us prospectively commencing in the first quarter of 2018. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements. Investments: In March 2016, amended guidance was issued to simplify the transition to the equity method of accounting. This standard eliminates the requirement that when an existing cost method investment qualifies for use of the equity method, an investor must restate its historical financial statements, as if the equity method had been used during all previous periods. Additionally, at the point an investment qualifies for the equity method, any unrealized gain or loss in accumulated other comprehensive income (loss) will be recognized through earnings. The amended guidance is effective for us prospectively commencing in the first quarter of 2018. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements. Derivatives and Hedging: In March 2016, amended guidance was issued for derivative instrument novations. The amendments clarify that a novation, a change in the counterparty, to a derivative instrument that has been designated as a hedging instrument does not, in and of itself, require dedesignation of that hedging relationships provided all other hedge accounting criteria continue to be met. The amended guidance is effective for us commencing in the first quarter of 2018, The amended guidance allows for either prospective or modified retrospective adoption. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements. Leases: In February 2016, amended guidance was issued for lease arrangements. The amended standard will require recognition on the balance sheet for all leases with terms longer than 12 months: a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. The amended guidance is effective for us commencing in the first quarter of 2020, on a modified retrospective basis. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements. Financial Instruments: In January 2016, amended guidance was issued that requires equity investments to be measured at fair value with changes in fair value recognized in net income and enhanced disclosures about those investments. This guidance also simplifies the impairment assessments of equity investments without readily determinable fair value. The investments that are accounted for under the equity method of accounting or result in consolidation of the investee are excluded from the scope of this amended guidance. The amended guidance will become effective for us commencing in the first quarter of 2019 and will be adopted through a cumulative-effect adjustment. Early adoption is not permitted except for certain provisions. We are currently evaluating the impact of this amended guidance on our consolidated financial statements. Business Combinations: In September 2015, amended guidance was issued for an acquirer’s accounting for measurement-period adjustments. The amended guidance eliminates the requirement that an acquirer in a business combination account for measurement-period adjustments retrospectively and instead requires that measurement-period adjustments be recognized during the period in which it determines the adjustment. In addition, the amended guidance requires that the acquirer record, in the same period’s financial statements, the effect on earnings of changes in depreciation, amortization, or other income effects, if any, as a result of the change to the provisional amounts, calculated as if the accounting had been completed at the acquisition date. The amended guidance is effective for us prospectively commencing in the first quarter of 2017. Early adoption is permitted. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements. Inventory: In July 2015, amended guidance was issued for the subsequent measurement of inventory. The amended guidance requires entities to measure inventory at the lower of cost or net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The requirement would replace the current lower of cost or market evaluation. Accounting guidance is unchanged for inventory measured using last-in, first-out (“LIFO”) or the retail method. The amended guidance will become effective for us commencing in the first quarter of 2018. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements. Fair Value Measurement: In May 2015, amended guidance was issued that limits disclosures and removes the requirement to categorize investments within the fair value hierarchy if the fair value of the investment is measured using the net asset value per share practical expedient. The amended guidance will become effective for us commencing in the first quarter of 2017. Early adoption is permitted. This amended guidance is primarily expected to affect our annual disclosures related to our pension benefits. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements. Fees Paid in a Cloud Computing Arrangement: In April 2015, amended guidance was issued for a customer’s accounting for fees paid in a cloud computing arrangement. The amended guidance requires customers to determine whether or not an arrangement contains a software license element. If the arrangement contains a software element, the related fees paid should be accounted for as an acquisition of a software license. If the arrangement does not contain a software license, it is accounted for as a service contract. The amended guidance will become effective for us commencing in the first quarter of 2017. Early adoption is permitted. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements. Debt Issuance Costs: In April 2015, amended guidance was issued for the balance sheet presentation of debt issuance costs. The amended guidance requires debt issuance costs related to a recognized debt liability to be reported in the balance sheet as a direct deduction from the carrying amount of that debt liability. The recognition and measurement guidance for debt issuance costs are not affected by the amended guidance. In August 2015, a clarification was added to this amended guidance that debt issuance costs related to line-of-credit arrangements can continue to be deferred and presented as an asset on the balance sheet. The amended guidance will become effective for us commencing in the first quarter of 2017. Early adoption is permitted. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements. Consolidation: In February 2015, amended guidance was issued for consolidating legal entities in which a reporting entity holds a variable interest. The amended guidance modifies the evaluation of whether limited partnerships and similar legal entities are VIEs and changes the consolidation analysis of reporting entities that are involved with VIEs that have fee arrangements and related party relationships. The amended guidance will become effective for us commencing in the first quarter of 2017. Early adoption is permitted. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements. Revenue Recognition: In May 2014, amended guidance was issued for recognizing revenue from contracts with customers. The amended guidance eliminates industry specific guidance and applies to all companies. Revenues will be recognized when an entity satisfies a performance obligation by transferring control of a promised good or service to a customer in an amount that reflects the consideration to which the entity expects to be entitled for that good or service. Revenue from a contract that contains multiple performance obligations is allocated to each performance obligation generally on a relative standalone selling price basis. The amended guidance also requires additional quantitative and qualitative disclosures. In March 2016, amended guidance was issued to clarify implementation guidance on principal versus agent considerations. In April 2016, another amended guidance was issued to permit an entity, as an accounting policy election, to account for shipping and handling activities that occur after the customer has obtained control of a good as an activity to fulfill the promise to transfer the good. The April 2016 amendment also provided clarifications on determining whether a promised license provides a customer with a right to use or a right to access an entity’s intellectual property. These amended standards are all effective for us commencing in the first quarter of 2019 and allow for either full retrospective adoption or modified retrospective adoption. Early adoption is permitted but not prior to our first quarter of 2018. We are currently evaluating the impact of this amended guidance on our consolidated financial statements.

Significant Accounting Policies

Nature of Operations: McKesson Corporation (“McKesson,” the “Company,” the “Registrant” or “we” and other similar pronouns) delivers a comprehensive offering of pharmaceuticals and medical supplies and provides services to help our customers improve the efficiency and effectiveness of their healthcare operations. We manage our business through two operating segments, McKesson Distribution Solutions and McKesson Technology Solutions, as further described in Financial Note 27, “Segments of Business.”

Basis of Presentation: The consolidated financial statements and accompanying notes are prepared in accordance with U. S. generally accepted accounting principles (“GAAP”). The consolidated financial statements of McKesson include the financial statements of all wholly-owned subsidiaries and majority-owned or controlled companies. For those consolidated subsidiaries where our ownership is less than 100%, the portion of the net income or loss allocable to the noncontrolling interests is reported as “Net Income Attributable to Noncontrolling Interests” on the consolidated statements of operations. All significant intercompany balances and transactions have been eliminated in consolidation.

We consider ourselves to control an entity if we are the majority owner of and have voting control over such entity. We also assess control through means other than voting rights (“variable interest entities” or “VIEs”) and determine which business entity is the primary beneficiary of the VIE. We consolidate VIEs when it is determined that we are the primary beneficiary of the VIE. Investments in business entities in which we do not have control, but have the ability to exercise significant influence over operating and financial policies, are accounted for using the equity method and our proportionate share of income or loss is recorded in other income, net. Equity investments in non-publicly traded entities are primarily accounted for using the cost method. Intercompany transactions and balances have been eliminated.

Fiscal Period: The Company’s fiscal year begins on April 1 and ends on March 31. Unless otherwise noted, all references to a particular year shall mean the Company’s fiscal year.

Reclassifications: Certain prior year amounts have been reclassified to conform to the current year presentation.

Use of Estimates: The preparation of financial statements in conformity with U.S. GAAP requires that we make estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying notes. Actual amounts could differ from those estimated amounts.

Cash and Cash Equivalents: All highly liquid debt and money market instruments purchased with original maturity of three months or less at the date of acquisition are included in cash and cash equivalents.

Cash equivalents, which are available-for-sale, are carried at fair value. Cash equivalents are primarily invested in AAA rated prime and U.S. government money market funds denominated in U.S. dollars, AAA rated prime money market funds denominated in Euros, overnight repurchase agreements collateralized by U.S. government securities, Canadian government securities and/or securities that are guaranteed or sponsored by the U.S. government and an AAA rated prime money market fund denominated in British pound sterling.

The remaining cash and cash equivalents are deposited with several financial institutions. Deposits may exceed the amounts insured by the Federal Deposit Insurance Corporation in the U.S. and similar deposit insurance programs in other jurisdictions. We mitigate the risk of our short-term investment portfolio by depositing funds with reputable financial institutions and monitoring risk profiles and investment strategies of money market funds.

Restricted Cash: Cash that is subject to legal restrictions or is unavailable for general operating purposes is classified as restricted cash and is included within “Prepaid expenses and other” and “Other Noncurrent Assets” in the consolidated balance sheets. At March 31, 2016, our restricted cash balance was $939 million, which represents cash paid into the escrow accounts for acquisitions that closed on April 1, 2016. There was no material restricted cash balance at March 31, 2015.

Marketable Securities Available-for-Sale: We carry our marketable securities, which are available-for-sale, at fair value and they are included in prepaid expenses and other in the consolidated balance sheets. The unrealized gains and losses, net of the related tax effect, computed in marking these securities to market have been reported within stockholders’ equity. At March 31, 2016 and 2015, marketable securities were not material.

In determining whether an other-than-temporary decline in market value has occurred, we consider the duration that, and extent to which, the fair value of the investment is below its cost, the financial condition and future prospects of the issuer or underlying collateral of a security, and our intent and ability to retain the security in order to allow for an anticipated recovery in fair value. Other-than-temporary declines in fair value from amortized cost for available-for-sale equity securities that we intend to sell or would more likely than not be required to sell before the expected recovery of the amortized cost basis are charged to other income, net, in the period in which the loss occurs.

Concentrations of Credit Risk and Receivables: Our trade receivables are subject to a concentration of credit risk with customers primarily in our Distribution Solutions segment. During 2016, sales to our ten largest customers, including group purchasing organizations (“GPOs”) accounted for approximately 52.4% of our total consolidated revenues. Sales to our largest customer, CVS Health (“CVS”), accounted for approximately 20.3% of our total consolidated revenues. At March 31, 2016, trade accounts receivable from our ten largest customers were approximately 32% of total trade accounts receivable. Accounts receivable from CVS were approximately 18% of total trade accounts receivable. As a result, our sales and credit concentration is significant. We also have agreements with GPOs, each of which functions as a purchasing agent on behalf of member hospitals, pharmacies and other healthcare providers, as well as with government entities and agencies. The accounts receivables balances are with individual members of the GPOs, and therefore no significant concentration of credit risk exists. A default in payment, a material reduction in purchases from these or any other large customers, or the loss of a large customer or customer groups could have a material adverse impact on our financial condition, results of operations and liquidity. In addition, trade receivables are subject to a concentration of credit risk with customers in the institutional, retail and healthcare provider sectors, which can be affected by a downturn in the economy and changes in reimbursement policies. This credit risk is mitigated by the size and diversity of the customer base as well as its geographic dispersion. We estimate the receivables for which we do not expect full collection based on historical collection rates and ongoing evaluations of the creditworthiness of our customers. An allowance is recorded in our consolidated financial statements for these amounts.

Financing Receivables: We assess and monitor credit risk associated with financing receivables, namely lease and notes receivables, through regular review of our collection experience in determining our allowance for loan losses. On an ongoing basis, we also evaluate credit quality of our financing receivables utilizing aging of receivables and write-offs, as well as considering existing economic conditions, to determine if an allowance is necessary. Financing receivables are derecognized if legal title to them has been transferred and all related risks and rewards incidental to ownership have passed to the buyer. As of March 31, 2016 and 2015, financing receivables and the related allowance were not material to our consolidated financial statements.

Inventories: We report inventories at the lower of cost or market (“LCM”). Inventories for our Distribution Solutions segment consist of merchandise held for resale. For our Distribution Solutions segment, the majority of the cost of domestic inventories is determined using the last-in, first-out (“LIFO”) method. The majority of the cost of inventories held in foreign locations is based on weighted average purchase prices using the first-in, first-out method (“FIFO”). Technology Solutions segment inventories consist of computer hardware with cost generally determined by the standard cost method, which approximates average cost. Rebates, cash discounts, and other incentives received from vendors are recognized within cost of sales upon the sale of the related inventory.

The LIFO method was used to value approximately 74% and 73% of our inventories at March 31, 2016 and 2015. If we had used the FIFO method of inventory valuation, which approximates current replacement costs, inventories would have been approximately $1,012 million and $768 million higher than the amounts reported at March 31, 2016 and 2015, respectively. These amounts are equivalent to our LIFO reserves. Our LIFO valuation amount includes both pharmaceutical and non-pharmaceutical products. In 2016, 2015 and 2014, we recognized LIFO related expenses of $244 million, $337 million and $311 million in cost of sales within our consolidated statements of operations. A LIFO expense is recognized when the net effect of price increases on pharmaceutical and non-pharmaceutical products held in inventory exceeds the impact of price declines, including the effect of branded pharmaceutical products that have lost market exclusivity. A LIFO credit is recognized when the net effect of price declines exceeds the impact of price increases on pharmaceutical and non-pharmaceutical products held in inventory.

We believe that the average inventory costing method provides a reasonable estimation of the current cost of replacing inventory (i.e., “market”). As such, our LIFO inventory is valued at the lower of LIFO or market. Due to cumulative net price deflation from 2005 to 2013, we had a lower-of-cost or market (“LCM”) reserve of $60 million at March 31, 2013 which reduced pharmaceutical inventories at LIFO to market. During 2014, the LCM reserve of $60 million was released, resulting in an increase in gross profit. As of March 31, 2016 and 2015, inventories at LIFO did not exceed market.

Shipping and Handling Costs: We include costs to pack and deliver inventory to our customers in selling, distribution and administrative expenses. Shipping and handling costs of $789 million, $819 million, $535 million were included in our selling, distribution and administrative expenses in 2016, 2015 and 2014.

Property, Plant and Equipment: We state our property, plant and equipment (“PPE”) at cost and depreciate them under the straight-line method at rates designed to distribute the cost of PPE over estimated service lives ranging from one to thirty years. When certain events or changes in operating conditions occur, an impairment assessment may be performed on the recoverability of the carrying amounts.

Goodwill: Goodwill is tested for impairment on an annual basis in the fourth quarter or more frequently if indicators for potential impairment exist. Impairment testing is conducted at the reporting unit level, which is generally defined as a component, one level below our Distribution Solutions and Technology Solutions operating segments, for which discrete financial information is available and segment management regularly reviews the operating results of that unit.

The first step in goodwill testing requires us to compare the estimated fair value of a reporting unit to its carrying value. This step may be performed utilizing either a qualitative or quantitative assessment. If the carrying value of the reporting unit is lower than its estimated fair value, no further evaluation is necessary. If the carrying value of the reporting unit is higher than its estimated fair value, the second step must be performed to measure the amount of impairment loss. Under the second step, the implied fair value of goodwill is calculated in a hypothetical analysis by subtracting the fair value of all assets and liabilities of the reporting unit, including any unrecognized intangible assets, from the fair value of the reporting unit calculated in the first step of the impairment test. If the carrying value of goodwill for the reporting unit exceeds the implied fair value of goodwill, an impairment charge is recorded for that excess.

To estimate the fair value of our reporting units, we use a combination of the market approach and the income approach. Under the market approach, we estimate fair value by comparing the business to similar businesses or guideline companies whose securities are actively traded in public markets. Under the income approach, we use a discounted cash flow model in which cash flows anticipated over several periods, plus a terminal value at the end of that time horizon, are discounted to their present value using an appropriate expected rate of return. The discount rate used for cash flows reflects capital market conditions and the specific risks associated with the business. In addition, we compare the aggregate of the reporting units’ fair value to the Company’s market capitalization as a further corroboration of the fair values. The testing requires a complex series of assumptions and judgment by management in projecting future operating results, selecting guideline companies for comparisons and assessing risks. The use of alternative assumptions and estimates could affect the fair values and change the impairment determinations.

Intangible Assets: Currently all of our intangible assets are subject to amortization and are amortized based on the pattern of their economic consumption or on a straight-line basis over their estimated useful lives, ranging from one to thirty-eight years. We review intangible assets for impairment whenever events or changes in circumstances indicate that the carrying value of the assets may not be recoverable. Determination of recoverability is based on the lowest level of identifiable estimated future undiscounted cash flows resulting from use of the asset and its eventual disposition. Measurement of any impairment loss is based on the excess of the carrying value of the asset over its fair market value.

Capitalized Software Held for Sale: Development costs for software held for sale, which primarily pertain to our Technology Solutions segment, are capitalized once a project has reached the point of technological feasibility. Completed projects are amortized after reaching the point of general availability using the straight-line method based on an estimated useful life of approximately three years. At each balance sheet date, or earlier if an indicator of an impairment exists, we evaluate the recoverability of unamortized capitalized software costs based on estimated future undiscounted revenues net of estimated related costs over the remaining amortization period.

Capitalized Software Held for Internal Use: We capitalize costs of software held for internal use during the application development stage of a project and amortize those costs over their estimated useful lives ranging from one to ten years. As of March 31, 2016 and 2015, capitalized software held for internal use was $435 million, net of accumulated amortization of $1,130 million and $1,112 million, and was included in other assets in the consolidated balance sheets.

Insurance Programs: Under our insurance programs, we seek to obtain coverage for catastrophic exposures as well as those risks required to be insured by law or contract. It is our policy to retain a significant portion of certain losses primarily related to workers’ compensation and comprehensive general, product and vehicle liability. Provisions for losses expected under these programs are recorded based upon our estimate of the aggregate liability for claims incurred as well as for claims incurred but not yet reported. Such estimates utilize certain actuarial assumptions followed in the insurance industry.

Revenue Recognition:

Distribution Solutions

Revenues for our Distribution Solutions segment are recognized when persuasive evidence of an arrangement exists, product is delivered and title passes to the customer or when services have been rendered and there are no further obligations to the customer, the price is fixed or determinable, and collection of the amounts are reasonably assured.

Revenues for our Distribution Solutions segment include large volume sales of pharmaceuticals primarily to a limited number of large customers who warehouse their own products. We order bulk product from the manufacturer, receive and process the product primarily through our central distribution facility and deliver the bulk product (generally in the same form as received from the manufacturer) directly to our customers’ warehouses. We also record revenues for direct store deliveries of shipments from the manufacturer to our customers. We assume the primary liability to the manufacturer for these products.

Revenues are recorded gross when we are the primary party obligated in the transaction, take title to and possession of the inventory, are subject to inventory risk, have latitude in establishing prices, assume the risk of loss for collection from customers as well as delivery or return of the product, are responsible for fulfillment and other customer service requirements, or the transactions have several but not all of these indicators.

Revenues are recorded net of sales returns, allowances, rebates and other incentives. Our sales return policy generally allows customers to return products only if they can be resold for value or returned to suppliers for credit. Sales returns are accrued based on estimates at the time of sale to the customer. Sales returns from customers were approximately $3.1 billion in 2016, $2.7 billion in 2015 and $1.9 billion in 2014. Taxes collected from customers and remitted to governmental authorities are presented on a net basis; that is, they are excluded from revenues.

Our Distribution Solutions segment also engages in multiple-element arrangements, which may contain a combination of various products and services. Revenue from a multiple-element arrangement is allocated to the separate elements based on their relative selling price and recognized in accordance with the revenue recognition criteria applicable to each element. Relative selling price is determined based on vendor-specific objective evidence (“VSOE”) of selling price, if available, third-party evidence (“TPE”), if VSOE of selling price is not available, or estimated selling price (“ESP”), if neither VSOE of selling price nor TPE is available.

Technology Solutions

Revenues for our Technology Solutions segment are generated primarily by licensing software and software systems (consisting of software, hardware and maintenance support), providing software as a service (“Saas”) or SaaS-based solutions and providing claims processing, outsourcing and professional services. Revenue for this segment is recognized as follows:

Software systems are marketed under information systems agreements as well as service agreements. Perpetual software arrangements are recognized at the time of delivery or under the percentage-of-completion method if the arrangements require significant production, modification or customization of the software. Contracts accounted for under the percentage-of-completion method are generally measured based on the ratio of labor hours incurred to date to total estimated labor hours to be incurred. Changes in estimates to complete and revisions in overall profit estimates on these contracts are charged to earnings in the period in which they are determined. We accrue for contract losses if and when the current estimate of total contract costs exceeds total contract revenue.

Revenue from time-based software license agreements is recognized ratably over the term of the agreement. Software implementation fees are recognized as the work is performed or under the percentage-of-completion method. Maintenance and support agreements are marketed under annual or multi-year agreements and are recognized ratably over the period covered by the agreements. Hardware revenues are generally recognized upon delivery.

SaaS-based subscription, content and transaction processing fees are generally marketed under annual and multi-year agreements and are recognized ratably over the contracted terms beginning on the service start date for fixed fee arrangements and recognized as transactions are performed beginning on the service start date for per-transaction fee arrangements. Remote processing service fees are recognized monthly as the service is performed. Outsourcing service revenues are recognized as the service is performed.

We also offer certain products on an application service provider basis, making our software functionality available on a remote hosting basis from our data centers. The data centers provide system and administrative support, as well as hosting services. Revenue on products sold on an application service provider basis is recognized on a monthly basis over the term of the contract beginning on the service start date of products hosted.

This segment engages in multiple-element arrangements, which may contain any combination of software, hardware, implementation, SaaS-based offerings, consulting services or maintenance services. For multiple-element arrangements that do not include software, revenue is allocated to the separate elements based on their relative selling price and recognized in accordance with the revenue recognition criteria applicable to each element. Relative selling price is determined based on VSOE of selling price if available, TPE, if VSOE of selling price is not available, or ESP if neither VSOE of selling price nor TPE is available. For multiple-element arrangements accounted for in accordance with specific software accounting guidance when some elements are delivered prior to others in an arrangement and VSOE of fair value exists for the undelivered elements, revenue for the delivered elements is recognized upon delivery of such items. The segment establishes VSOE for hardware and implementation and consulting services based on the price charged when sold separately, and for maintenance services, based on renewal rates offered to customers. Revenue for the software element is recognized under the residual method only when fair value has been established for all of the undelivered elements in an arrangement. If fair value cannot be established for any undelivered element, all of the arrangement’s revenue is deferred until the delivery of the last element or until the fair value of the undelivered element is determinable. For multiple-element arrangements with both software elements and nonsoftware elements, arrangement consideration is allocated between the software elements as a whole and nonsoftware elements. The segment then further allocates consideration to the individual elements within the software group, and revenue is recognized for all elements under the applicable accounting guidance and our policies described above.

Supplier Incentives: Fees for service and other incentives received from suppliers, relating to the purchase or distribution of inventory, are generally reported as a reduction to cost of sales. We consider these fees and other incentives to represent product discounts and as a result, the amounts are recognized within cost of sales upon the sale of the related inventory.

Supplier Reserves: We establish reserves against amounts due from suppliers relating to various fees for services and price and rebate incentives, including deductions taken against payments otherwise due to them. These reserve estimates are established based on judgment after considering the status of current outstanding claims, historical experience with the suppliers, the specific incentive programs and any other pertinent information available. We evaluate the amounts due from suppliers on a continual basis and adjust the reserve estimates when appropriate based on changes in factual circumstances. All adjustments to supplier reserves are included in cost of sales. The ultimate outcome of any outstanding claims may be different than our estimate. As of March 31, 2016 and 2015 supplier reserves were $144 million and $167 million. All of the supplier reserves at March 31, 2016 and 2015 pertain to our Distribution Solutions segment.

Income Taxes: We account for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial statements and the tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Tax benefits from uncertain tax positions are recognized when it is more likely than not that the position will be sustained upon examination, including resolutions of any related appeals or litigation processes, based on the technical merits. The amount recognized is measured as the largest amount of tax benefit that is greater than 50 percent likely of being realized upon effective settlement. Deferred taxes are not provided on undistributed earnings of our foreign operations that are considered to be permanently reinvested.

Foreign Currency Translation: The reporting currency of the Company and its subsidiaries is the U.S. dollar. Our foreign subsidiaries generally consider their local currency to be their functional currency. Foreign currency-denominated assets and liabilities of these foreign subsidiaries are translated into U.S. dollars at year-end exchange rates and revenues and expenses are translated at average exchange rates during the corresponding period, and stockholders’ equity accounts are primarily translated at historical exchange rates. Foreign currency translation adjustments are included in other comprehensive income or loss in the statements of consolidated comprehensive income, and the cumulative effect is included in the stockholders’ equity section of the consolidated balance sheets. Realized gains and losses from currency exchange transactions are recorded in operating expenses in the consolidated statements of operations and were not material to our consolidated results of operations in 2016, 2015 or 2014. We release cumulative translation adjustment from stockholders’ equity into net income as a gain or loss only upon complete or substantially complete liquidation of a controlling interest in a subsidiary or a group of assets within a foreign entity. We also release all or a pro rata portion of the cumulative translation adjustment into net income upon the sale of an equity method investment that is a foreign entity.

Derivative Financial Instruments: Derivative financial instruments are used principally in the management of foreign currency exchange and interest rate exposures and are recorded on the consolidated balance sheets at fair value. If a derivative is designated as a fair value hedge, the changes in the fair value of the derivative and of the hedged item attributable to the hedged risk are recognized as a charge or credit to earnings. If the derivative is designated as a cash flow hedge, the effective portions of changes in the fair value of the derivative are included in other comprehensive income or loss in the statements of consolidated comprehensive income, and the cumulative effect is included in the stockholders’ equity section of the consolidated balance sheets. The cumulative changes in fair value are reclassified to the consolidated statements of operations when the hedged item affects earnings. We periodically evaluate hedge effectiveness, and ineffective portions of changes in the fair value of cash flow hedges are recognized as a charge or credit to earnings. Derivative instruments not designated as hedges are marked-to-market at the end of each accounting period with the change included in earnings.

Comprehensive Income: Comprehensive income consists of two components, net income and other comprehensive income. Other comprehensive income refers to revenue, expenses, and gains and losses that under GAAP are recorded as an element of stockholders’ equity but are excluded from net income. Our other comprehensive income primarily consists of foreign currency translation adjustments from those subsidiaries where the local currency is the functional currency, unrealized gains and losses on cash flow hedges, as well as unrealized gains and losses on retirement-related benefit plans.

Noncontrolling Interests and Redeemable Noncontrolling Interests: Noncontrolling interests represent the portion of profit or loss, net assets and comprehensive income that is not allocable to McKesson Corporation. In 2016 and 2015, net income attributable to noncontrolling interests primarily represents guaranteed dividends and recurring compensation that McKesson is obligated to pay to the noncontrolling shareholders of Celesio AG (“Celesio”). Noncontrolling interests with redemption features, such as put rights, that are not solely within the Company’s control are considered redeemable noncontrolling interests. Redeemable noncontrolling interests are presented outside of Stockholders’ Equity on our consolidated balance sheet. Refer to Financial Note 10, “Noncontrolling Interests and Redeemable Noncontrolling Interests,” for more information.

Share-Based Compensation: We account for all share-based compensation transactions using a fair-value based measurement method. The share-based compensation expense, for the portion of the awards that is ultimately expected to vest, is recognized on a straight-line basis over the requisite service period. The compensation expense recognized has been classified in the consolidated statements of operations or capitalized on the consolidated balance sheets in the same manner as cash compensation paid to our employees.

Loss Contingencies: We are subject to various claims, including claims with customers and vendors, pending and potential legal actions for damages, investigations relating to governmental laws and regulations and other matters arising out of the normal conduct of our business. When a loss is considered probable and reasonably estimable, we record a liability in the amount of our best estimate for the ultimate loss. However, the likelihood of a loss with respect to a particular contingency is often difficult to predict and determining a meaningful estimate of the loss or a range of loss may not be practicable based on the information available and the potential effect of future events and decisions by third parties that will determine the ultimate resolution of the contingency. Moreover, it is not uncommon for such matters to be resolved over many years, during which time relevant developments and new information must be reevaluated at least quarterly to determine both the likelihood of potential loss and whether it is possible to reasonably estimate a range of possible loss. When a material loss is probable but a reasonable estimate cannot be made, disclosure of the proceeding is provided.

Disclosure is also provided when it is reasonably possible that a loss will be incurred or when it is reasonably possible that the amount of a loss will exceed the recorded provision. We review all contingencies at least quarterly to determine whether the likelihood of loss has changed and to assess whether a reasonable estimate of the loss or range of the loss can be made. As discussed above, development of a meaningful estimate of loss or a range of potential loss is complex when the outcome is directly dependent on negotiations with or decisions by third parties, such as regulatory agencies, the court system and other interested parties. Such factors bear directly on whether it is possible to reasonably estimate a range of potential loss and boundaries of high and low estimate.

Business Combinations: We account for acquired businesses using the acquisition method of accounting, which requires that once control is obtained of a business, 100% of the assets acquired and liabilities assumed, including amounts attributed to noncontrolling interests, be recorded at the date of acquisition at their respective fair values. Any excess of the purchase price over the estimated fair values of the net assets acquired is recorded as goodwill. Acquisition-related expenses and related restructuring costs are expensed as incurred.

Several valuation methods may be used to determine the fair value of assets acquired and liabilities assumed. For intangible assets, we typically use the income method. This method starts with a forecast of all of the expected future net cash flows for each asset. These cash flows are then adjusted to present value by applying an appropriate discount rate that reflects the risk factors associated with the cash flow streams. Some of the more significant estimates and assumptions inherent in the income method or other methods include the amount and timing of projected future cash flows, the discount rate selected to measure the risks inherent in the future cash flows and the assessment of the asset’s life cycle and the competitive trends impacting the asset, including consideration of any technical, legal, regulatory, or economic barriers to entry. Determining the useful life of an intangible asset also requires judgment as different types of intangible assets will have different useful lives and certain assets may even be considered to have indefinite useful lives.

Recently Adopted Accounting Pronouncements

Deferred Income Taxes: In November 2015, amended guidance was issued for the balance sheet classification of deferred income taxes. The amended guidance requires the classification of all deferred tax assets and liabilities as noncurrent on the balance sheet instead of separating deferred taxes into current and noncurrent amounts. The amended guidance would have been effective for us commencing in the first quarter of 2018, however, early adoption was permitted. We early adopted this amended guidance in the fourth quarter of 2016 on a prospective basis. As a result, we reclassified current net deferred tax liabilities of approximately $2 billion on our consolidated balance sheet as of March 31, 2016. Our March 31, 2015 balances were not retrospectively adjusted. The adoption of this guidance had no impact on our condensed consolidated statements of earnings, comprehensive income or cash flows. This amended guidance only resulted in a change in presentation of our deferred income taxes on our consolidated balance sheet as of March 31, 2016.

Discontinued Operations: In the first quarter of 2016, we adopted amended guidance for reporting of discontinued operations and disclosures of disposals of components. The amended guidance revises the criteria for disposals to qualify as discontinued operations and permits significant continuing involvement and continuing cash flows with the discontinued operation. In addition, the amended guidance requires additional disclosures for discontinued operations and new disclosures for individually material disposal transactions that do not meet the definition of a discontinued operation. Refer to Financial Note 5, “Divestiture of Businesses,” for more information regarding the impact of this amended guidance on our consolidated financial statements.

Cumulative Translation Adjustment: In the first quarter of 2015, we adopted amended guidance for a parent’s accounting for the cumulative translation adjustment upon derecognition of certain subsidiaries or group of assets within a foreign entity or of an investment in a foreign entity. The amended guidance requires the release of any cumulative translation adjustment into net income only upon complete or substantially complete liquidation of a controlling interest in a subsidiary or a group of assets within a foreign entity. Also, it requires the release of all or a pro rata portion of the cumulative translation adjustment to net income in the case of sale of an equity method investment that is a foreign entity. The adoption of this amended guidance did not have a material effect on our consolidated financial statements.

Recently Issued Accounting Pronouncements Not Yet Adopted

Share-Based Payments: In March 2016, amended guidance was issued for employee share-based payment awards. The amended guidance makes several modifications related to the accounting for forfeitures, employer tax withholding on share-based compensation and excess tax benefits or deficiencies. The amended guidance also clarifies the statement of cash flows presentation for share-based awards. The amended guidance is effective for us prospectively commencing in the first quarter of 2018. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements.

Investments: In March 2016, amended guidance was issued to simplify the transition to the equity method of accounting. This standard eliminates the requirement that when an existing cost method investment qualifies for use of the equity method, an investor must restate its historical financial statements, as if the equity method had been used during all previous periods. Additionally, at the point an investment qualifies for the equity method, any unrealized gain or loss in accumulated other comprehensive income (loss) will be recognized through earnings. The amended guidance is effective for us prospectively commencing in the first quarter of 2018. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements.

Derivatives and Hedging: In March 2016, amended guidance was issued for derivative instrument novations. The amendments clarify that a novation, a change in the counterparty, to a derivative instrument that has been designated as a hedging instrument does not, in and of itself, require dedesignation of that hedging relationships provided all other hedge accounting criteria continue to be met. The amended guidance is effective for us commencing in the first quarter of 2018, The amended guidance allows for either prospective or modified retrospective adoption. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements.

Leases: In February 2016, amended guidance was issued for lease arrangements. The amended standard will require recognition on the balance sheet for all leases with terms longer than 12 months: a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. The amended guidance is effective for us commencing in the first quarter of 2020, on a modified retrospective basis. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements.

Financial Instruments: In January 2016, amended guidance was issued that requires equity investments to be measured at fair value with changes in fair value recognized in net income and enhanced disclosures about those investments. This guidance also simplifies the impairment assessments of equity investments without readily determinable fair value. The investments that are accounted for under the equity method of accounting or result in consolidation of the investee are excluded from the scope of this amended guidance. The amended guidance will become effective for us commencing in the first quarter of 2019 and will be adopted through a cumulative-effect adjustment. Early adoption is not permitted except for certain provisions. We are currently evaluating the impact of this amended guidance on our consolidated financial statements.

Business Combinations: In September 2015, amended guidance was issued for an acquirer’s accounting for measurement-period adjustments. The amended guidance eliminates the requirement that an acquirer in a business combination account for measurement-period adjustments retrospectively and instead requires that measurement-period adjustments be recognized during the period in which it determines the adjustment. In addition, the amended guidance requires that the acquirer record, in the same period’s financial statements, the effect on earnings of changes in depreciation, amortization, or other income effects, if any, as a result of the change to the provisional amounts, calculated as if the accounting had been completed at the acquisition date. The amended guidance is effective for us prospectively commencing in the first quarter of 2017. Early adoption is permitted. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements.

Inventory: In July 2015, amended guidance was issued for the subsequent measurement of inventory. The amended guidance requires entities to measure inventory at the lower of cost or net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The requirement would replace the current lower of cost or market evaluation. Accounting guidance is unchanged for inventory measured using last-in, first-out (“LIFO”) or the retail method. The amended guidance will become effective for us commencing in the first quarter of 2018. Early adoption is permitted. We are currently evaluating the impact of this amended guidance on our consolidated financial statements.

Fair Value Measurement: In May 2015, amended guidance was issued that limits disclosures and removes the requirement to categorize investments within the fair value hierarchy if the fair value of the investment is measured using the net asset value per share practical expedient. The amended guidance will become effective for us commencing in the first quarter of 2017. Early adoption is permitted. This amended guidance is primarily expected to affect our annual disclosures related to our pension benefits. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements.

Fees Paid in a Cloud Computing Arrangement: In April 2015, amended guidance was issued for a customer’s accounting for fees paid in a cloud computing arrangement. The amended guidance requires customers to determine whether or not an arrangement contains a software license element. If the arrangement contains a software element, the related fees paid should be accounted for as an acquisition of a software license. If the arrangement does not contain a software license, it is accounted for as a service contract. The amended guidance will become effective for us commencing in the first quarter of 2017. Early adoption is permitted. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements.

Debt Issuance Costs: In April 2015, amended guidance was issued for the balance sheet presentation of debt issuance costs. The amended guidance requires debt issuance costs related to a recognized debt liability to be reported in the balance sheet as a direct deduction from the carrying amount of that debt liability. The recognition and measurement guidance for debt issuance costs are not affected by the amended guidance. In August 2015, a clarification was added to this amended guidance that debt issuance costs related to line-of-credit arrangements can continue to be deferred and presented as an asset on the balance sheet. The amended guidance will become effective for us commencing in the first quarter of 2017. Early adoption is permitted. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements.

Consolidation: In February 2015, amended guidance was issued for consolidating legal entities in which a reporting entity holds a variable interest. The amended guidance modifies the evaluation of whether limited partnerships and similar legal entities are VIEs and changes the consolidation analysis of reporting entities that are involved with VIEs that have fee arrangements and related party relationships. The amended guidance will become effective for us commencing in the first quarter of 2017. Early adoption is permitted. We do not expect the adoption of this amended guidance to have a material effect on our consolidated financial statements.

Revenue Recognition: In May 2014, amended guidance was issued for recognizing revenue from contracts with customers. The amended guidance eliminates industry specific guidance and applies to all companies. Revenues will be recognized when an entity satisfies a performance obligation by transferring control of a promised good or service to a customer in an amount that reflects the consideration to which the entity expects to be entitled for that good or service. Revenue from a contract that contains multiple performance obligations is allocated to each performance obligation generally on a relative standalone selling price basis. The amended guidance also requires additional quantitative and qualitative disclosures. In March 2016, amended guidance was issued to clarify implementation guidance on principal versus agent considerations. In April 2016, another amended guidance was issued to permit an entity, as an accounting policy election, to account for shipping and handling activities that occur after the customer has obtained control of a good as an activity to fulfill the promise to transfer the good. The April 2016 amendment also provided clarifications on determining whether a promised license provides a customer with a right to use or a right to access an entity’s intellectual property. These amended standards are all effective for us commencing in the first quarter of 2019 and allow for either full retrospective adoption or modified retrospective adoption. Early adoption is permitted but not prior to our first quarter of 2018. We are currently evaluating the impact of this amended guidance on our consolidated financial statements.