Basis of Presentation and Summary of Significant Accounting Policies (Policies)	6 Months Ended
Dec. 31, 2018
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation Our condensed consolidated financial statements include the accounts of all majority-owned or controlled subsidiaries, and all significant intercompany transactions and amounts have been eliminated. References to "we," "our," and similar pronouns in these condensed consolidated financial statements refer to Cardinal Health, Inc. and its majority-owned or controlled subsidiaries unless the context requires otherwise. Our fiscal year ends on June 30. References to fiscal 2019 and 2018 in these condensed consolidated financial statements are to the fiscal years ending or ended June 30, 2019 and June 30, 2018, respectively. Our condensed consolidated financial statements have been prepared in accordance with the U.S. Securities and Exchange Commission ("SEC") instructions to Quarterly Reports on Form 10-Q and include the information and disclosures required by accounting principles generally accepted in the United States ("GAAP") for interim financial reporting. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect amounts reported in the condensed consolidated financial statements and accompanying notes. Actual amounts may differ from these estimated amounts. In our opinion, all adjustments necessary for a fair presentation of the condensed consolidated financial statements have been included. Except as disclosed elsewhere in this Form 10-Q, all such adjustments are of a normal and recurring nature. To conform to the current year presentation, certain prior year amounts have been reclassified. In addition, financial results presented for this fiscal 2019 interim period are not necessarily indicative of the results that may be expected for the full fiscal year ending June 30, 2019. These condensed consolidated financial statements are unaudited and, accordingly, should be read in conjunction with the audited consolidated financial statements and related notes contained in our Annual Report on Form 10-K for the fiscal year ended June 30, 2018 (the "2018 Form 10-K").
Recent Financial Accounting Standards	Recent Financial Accounting Standards In October 2018, the Financial Accounting Standards Board ("FASB") issued amended accounting guidance related to derivatives and hedging which permits the use of the Secured Overnight Financing Rate ("SOFR") Overnight Index Swap ("OIS") as a Benchmark Interest Rate for Hedge Accounting Purposes. This guidance will be effective for us in the first quarter of fiscal 2020 and must be applied on a prospective basis. We are currently evaluating the impact of adoption on our condensed consolidated financial statements. In March 2018, the FASB issued amended accounting guidance to codify SEC staff accounting bulletin 118 (“SAB 118”), which was issued in connection with the Tax Cuts and Jobs Act (the “Tax Act”) of December 2017. The guidance allows companies to use provisional estimates to record the effects of the Tax Act and also provides a measurement period (not to exceed one year from the date of enactment) to complete the accounting for the impacts of the Tax Act. We adopted this guidance in the second quarter of fiscal 2018 when it was initially issued as SAB 118. We completed our accounting for the impacts from enactment of the Tax Act during the three months ended December 31, 2018. Future adjustments to the financial statements may be necessary due to final Section 965 repatriation tax regulations, which were issued January 15, 2019, and any additional pending regulatory changes, the impact of which is being currently assessed, or will be assessed, as final regulations are issued. See Note 8 for additional information regarding income taxes. In June 2016, the FASB issued amended accounting guidance that will require entities to measure credit losses on trade and other receivables, held-to-maturity debt securities, loans and other instruments using an "expected credit loss" model that considers historical experience, current conditions and reasonable supportable forecasts. This guidance also requires that credit losses on available-for-sale debt securities with unrealized losses be recognized as allowances rather than as deductions in the amortized cost of the securities. This guidance will be effective for us in the first quarter of fiscal 2021. We are currently evaluating the impact of adoption on our condensed consolidated financial statements. In February 2016, the FASB issued amended accounting guidance that requires lessees to recognize most leases on the balance sheet as a lease liability and corresponding right-of-use asset. The guidance also requires disclosures that meet the objective of enabling financial statement users to assess the amount, timing and uncertainty of cash flows arising from leases. We will adopt this guidance when it is effective for us in the first quarter of fiscal 2020 and we expect to elect the practical expedient which will allow us to not apply the amended lease accounting guidance to comparative periods that will be presented. The majority of our lease spend relates to certain real estate with the remaining lease spend primarily related to equipment. We anticipate that the adoption of the amended lease guidance will result in an increase to the assets and liabilities on our condensed consolidated balance sheet, but we are continuing to evaluate the impact of this standard on our condensed consolidated financial statements and the methods of adoption. In May 2014, the FASB issued amended accounting guidance related to revenue recognition which we adopted in the first quarter of fiscal 2019 using the modified retrospective method and that we applied to customer contracts that were not completed as of June 30, 2018. The adoption of the amended accounting guidance did not have a material impact on our condensed consolidated financial statements. We did not record any material contract assets, contract liabilities, or deferred contract costs in our condensed consolidated balance sheets upon adopting the amended accounting guidance. As a result of adoption, assets recorded for the right to recover products from customers and the associated refund liabilities for return allowances were not material. Revenue in both segments is primarily related to the distribution of pharmaceutical and medical products, which we recognize at a point in time when title transfers to customers and we have no further obligation to provide services related to such merchandise. Service revenues are recognized over the period that services are provided to the customer. Revenues derived from services are not material for either segment for all periods presented. We are generally the principal in a transaction, therefore our revenue is primarily recorded on a gross basis. When we are a principal in a transaction, we have determined that we control the ability to direct the use of the product or service prior to transfer to a customer, are primarily responsible for fulfilling the promise to provide the product or service to our customer, have discretion in establishing prices, and ultimately control the transfer of the product or services provided to the customer. Revenue is recorded net of sales returns and allowances. Revenues are measured based on the amount of consideration that we expect to receive, reduced by estimates for return allowances, discounts, rebates and other variable consideration. Sales returns are recorded based on estimates using historical data. Shipping and handling costs are primarily included in distribution, selling, general and administrative ("SG&A") expenses in our condensed consolidated statements of earnings and include all delivery expenses as well as all costs to prepare the product for shipment to the end customer. Shipping and handling costs incurred after control has transferred to the customer are treated as fulfillment costs. We elected the practical expedient to expense costs to obtain a contract when incurred when the amortization period would have been one year or less. Additionally, we elected the practical expedients to not disclose the value of unsatisfied performance obligations for contracts with an original expected length of one year or less, contracts for which we recognize revenue at the amount to which we have the right to invoice for services performed and for contracts for which the variable consideration is allocated entirely to a wholly unsatisfied performance obligation or to a wholly unsatisfied promise to transfer a distinct good or service that forms part of a single performance obligation. See Note 14 for additional information regarding our disaggregation of revenue. In the first quarter of fiscal 2019, we adopted the following Accounting Standards Updates ("ASU"). ASU 2016-01 Financial Instruments: Recognition and Measurement of Financial Assets and Financial Liabilities; ASU 2018-03 Technical Corrections and Improvements to Financial Instruments; ASU 2016-15 Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments; ASU 2016-16 Income Taxes: Intra-Entity Transfers of Assets Other Than Inventory; and ASU 2017-12 Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities. The adoption of these ASUs did not have a material impact on our condensed consolidated financial statements.

Recent Financial Accounting Standards

In October 2018, the Financial Accounting Standards Board ("FASB") issued amended accounting guidance related to derivatives and hedging which permits the use of the Secured Overnight Financing Rate ("SOFR") Overnight Index Swap ("OIS") as a Benchmark Interest Rate for Hedge Accounting Purposes. This guidance will be effective for us in the first quarter of fiscal 2020 and must be applied on a prospective basis. We are currently evaluating the impact of adoption on our condensed consolidated financial statements.

In March 2018, the FASB issued amended accounting guidance to codify SEC staff accounting bulletin 118 (“SAB 118”), which was issued in connection with the Tax Cuts and Jobs Act (the “Tax Act”) of December 2017. The guidance allows companies to use provisional estimates to record the effects of the Tax Act and also provides a measurement period (not to exceed one year from the date of enactment) to complete the accounting for the impacts of the Tax Act. We adopted this guidance in the second quarter of fiscal 2018 when it was initially issued as SAB 118. We completed our accounting for the impacts from enactment of the Tax Act during the three months ended December 31, 2018. Future adjustments to the financial statements may be necessary due to final Section 965 repatriation tax regulations, which were issued January 15, 2019, and any additional pending regulatory changes, the impact of which is being currently assessed, or will be assessed, as final regulations are issued. See Note 8 for additional information regarding income taxes.

In June 2016, the FASB issued amended accounting guidance that will require entities to measure credit losses on trade and other receivables, held-to-maturity debt securities, loans and other instruments using an "expected credit loss" model that considers historical experience, current conditions and reasonable supportable forecasts. This guidance also requires that credit losses on available-for-sale debt securities with unrealized losses be recognized as allowances rather than as deductions in the amortized cost of the securities. This guidance will be effective for us in the first quarter of fiscal 2021. We are currently evaluating the impact of adoption on our condensed consolidated financial statements.

In February 2016, the FASB issued amended accounting guidance that requires lessees to recognize most leases on the balance sheet as a lease liability and corresponding right-of-use asset. The guidance also requires disclosures that meet the objective of enabling financial statement users to assess the amount, timing and uncertainty of cash flows arising from leases. We will adopt this guidance when it is effective for us in the first quarter of fiscal 2020 and we expect to elect the practical expedient which will allow us to not apply the amended lease accounting guidance to comparative periods that will be presented. The majority of our lease spend relates to certain real estate with the remaining lease spend primarily related to equipment. We anticipate that the adoption of the amended lease guidance will result in an increase to the assets and liabilities on our condensed consolidated balance sheet, but we are continuing to evaluate the impact of this standard on our condensed consolidated financial statements and the methods of adoption.

In May 2014, the FASB issued amended accounting guidance related to revenue recognition which we adopted in the first quarter of fiscal 2019 using the modified retrospective method and that we applied to customer contracts that were not completed as of June 30, 2018.

The adoption of the amended accounting guidance did not have a material impact on our condensed consolidated financial statements. We did not record any material contract assets, contract liabilities, or deferred contract costs in our condensed consolidated balance sheets upon adopting the amended accounting guidance. As a result of adoption, assets recorded for the right to recover products from customers and the associated refund liabilities for return allowances were not material.

Revenue in both segments is primarily related to the distribution of pharmaceutical and medical products, which we recognize at a point in time when title transfers to customers and we have no further obligation to provide services related to such merchandise. Service revenues are recognized over the period that services are provided to the customer. Revenues derived from services are not material for either segment for all periods presented.

We are generally the principal in a transaction, therefore our revenue is primarily recorded on a gross basis. When we are a principal in a transaction, we have determined that we control the ability to direct the use of the product or service prior to transfer to a customer, are primarily responsible for fulfilling the promise to provide the product or service to our customer, have discretion in establishing prices, and ultimately control the transfer of the product or services provided to the customer.

Revenue is recorded net of sales returns and allowances. Revenues are measured based on the amount of consideration that we expect to receive, reduced by estimates for return allowances, discounts, rebates and other variable consideration. Sales returns are recorded based on estimates using historical data. Shipping and handling costs are primarily included in distribution, selling, general and administrative ("SG&A") expenses in our condensed consolidated statements of earnings and include all delivery expenses as well as all costs to prepare the product for shipment to the end customer. Shipping and handling costs incurred after control has transferred to the customer are treated as fulfillment costs.

We elected the practical expedient to expense costs to obtain a contract when incurred when the amortization period would have been one year or less. Additionally, we elected the practical expedients to not disclose the value of unsatisfied performance obligations for contracts with an original expected length of one year or less, contracts for which we recognize revenue at the amount to which we have the right to invoice for services performed and for contracts for which the variable consideration is allocated entirely to a wholly unsatisfied performance obligation or to a wholly unsatisfied promise to transfer a distinct good or service that forms part of a single performance obligation. See Note 14 for additional information regarding our disaggregation of revenue.

In the first quarter of fiscal 2019, we adopted the following Accounting Standards Updates ("ASU"). ASU 2016-01 Financial Instruments: Recognition and Measurement of Financial Assets and Financial Liabilities; ASU 2018-03 Technical Corrections and Improvements to Financial Instruments; ASU 2016-15 Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments; ASU 2016-16 Income Taxes: Intra-Entity Transfers of Assets Other Than Inventory; and ASU 2017-12 Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities. The adoption of these ASUs did not have a material impact on our condensed consolidated financial statements.