Summary of Significant Accounting Policies	12 Months Ended
Summary of Significant Accounting Policies	Sep. 30, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The accompanying Consolidated Financial Statements and Notes to Consolidated Financial Statements of Becton, Dickinson and Company (the “Company” or "BD") have been prepared in accordance with U.S. generally accepted accounting principles ("U.S. GAAP"). Within the financial statements and tables presented, certain columns and rows may not add due to the use of rounded numbers for disclosure purposes. Percentages and earnings per share amounts presented are calculated from the underlying amounts. Our fiscal year ends on September 30. Principles of Consolidation The consolidated financial statements include the Company’s accounts and those of its majority-owned subsidiaries after the elimination of intercompany transactions. The Company has no material interests in variable interest entities. Cash Equivalents Cash equivalents consist of all highly liquid investments with a maturity of three months or less at time of purchase. Restricted Cash Restricted cash consists of cash restricted from withdrawal and usage and largely represents funds that are restricted for certain product liability matters assumed in the acquisition of C.R. Bard, Inc. ("Bard"), which are further discussed in Note 5. Trade Receivables The Company grants credit to customers in the normal course of business and the resulting trade receivables are stated at their net realizable value. The allowance for doubtful accounts represents the Company’s estimate of probable credit losses relating to trade receivables and is determined based on historical experience and other specific account data. Amounts are written off against the allowances for doubtful accounts when the Company determines that a customer account is uncollectable. Inventories Inventories are stated at the lower of approximate cost determined on the first-in, first-out basis or market. Property, Plant and Equipment Property, plant and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation and amortization are principally provided on the straight-line basis over estimated useful lives, which range from 20 to 45 years for buildings, four to 13 years for machinery and equipment and one to 20 years for leasehold improvements. Depreciation and amortization expense was $646 million, $633 million and $600 million in fiscal years 2020, 2019 and 2018, respectively. Goodwill and Other Intangible Assets The Company’s unamortized intangible assets include goodwill which arise from acquisitions of businesses. The Company currently reviews goodwill for impairment using quantitative models. Goodwill is reviewed at least annually for impairment at the reporting unit level, which is defined as an operating segment or one level below an operating segment, referred to as a component. The Company’s reporting units generally represent one level below reporting segments. Potential impairment of goodwill is generally identified by comparing the fair value of a reporting unit, estimated using an income approach, with its carrying value. The annual impairment review performed on July 1, 2020 indicated that all identified reporting units’ fair values exceeded their respective carrying values. Amortized intangible assets include developed technology assets which arise from acquisitions. These assets represent acquired intellectual property that is already technologically feasible upon the acquisition date or acquired in-process research and development assets that are completed subsequent to acquisition. Developed technology assets are generally amortized over periods ranging from 15 to 20 years, using the straight-line method. Customer relationship assets are generally amortized over periods ranging from 10 to 15 years, using the straight-line method. Other intangibles with finite useful lives, which include patents, are amortized over periods principally ranging from one to 40 years, using the straight-line method. Finite-lived intangible assets, including developed technology assets, are periodically reviewed when impairment indicators are present to assess recoverability from future operations using undiscounted cash flows. The carrying values of these finite-lived assets are compared to the undiscounted cash flows they are expected to generate and an impairment loss is recognized in operating results to the extent any finite-lived intangible asset’s carrying value exceeds its calculated fair value. Foreign Currency Translation Generally, foreign subsidiaries’ functional currency is the local currency of operations and the net assets of foreign operations are translated into U.S. dollars using current exchange rates. The U.S. dollar results that arise from such translation, as well as exchange gains and losses on intercompany balances of a long-term investment nature, are included in the foreign currency translation adjustments in Accumulated other comprehensive income (loss). Revenue Recognition The Company recognizes revenue from product sales when the customer obtains control of the product, which is generally upon shipment or delivery, depending on the delivery terms specified in the sales agreement. Revenues associated with certain instruments and equipment for which installation is complex, and therefore significantly affects the customer’s ability to use and benefit from the product, are recognized upon customer acceptance of these installed products. Revenue for certain service arrangements, including extended warranty and software maintenance contracts, is recognized ratably over the contract term. When arrangements include multiple performance obligations, the total transaction price of the contract is allocated to each performance obligation based on the estimated relative standalone selling prices of the promised goods or services underlying each performance obligation. Variable consideration such as rebates, sales discounts and sales returns are estimated and treated as a reduction of revenue in the same period the related revenue is recognized. These estimates are based on contractual terms, historical practices, and current trends, and are adjusted as new information becomes available. Revenues exclude any taxes that the Company collects from customers and remits to tax authorities. Equipment lease transactions with customers are evaluated and classified as either operating or sales-type leases. Generally, these arrangements are accounted for as operating leases and therefore, revenue is recognized at the contracted rate over the rental period defined within the customer agreement. Additional disclosures regarding the Company's accounting for revenue recognition are provided in Note 6. Shipping and Handling Costs The Company considers its shipping and handling costs to be contract fulfillment costs and records them within Selling and administrative expense. Shipping expense was $551 million, $511 million and $479 million in 2020, 2019 and 2018, respectively. Derivative Financial Instruments All derivatives are recorded in the balance sheet at fair value and changes in fair value are recognized currently in earnings unless specific hedge accounting criteria are met. Any deferred gains or losses associated with derivative instruments are recognized in income in the period in which the underlying hedged transaction is recognized. Additional disclosures regarding the Company's accounting for derivative instruments are provided in Note 14. Income Taxes The Company has reviewed its needs in the United States for possible repatriation of undistributed earnings of its foreign subsidiaries and continues to invest foreign subsidiaries earnings outside of the United States to fund foreign investments or meet foreign working capital and property, plant and equipment expenditure needs. As a result, the Company is permanently reinvested with respect to all of its historical foreign earnings as of September 30, 2020. Deferred taxes are not provided on undistributed earnings of foreign subsidiaries that are indefinitely reinvested. The determination of the amount of the unrecognized deferred tax liability related to the undistributed earnings is not practicable because of the complexities associated with its hypothetical calculation. The Company conducts business and files tax returns in numerous countries and currently has tax audits in progress in a number of tax jurisdictions. In evaluating the exposure associated with various tax filing positions, the Company records accruals for uncertain tax positions based on the technical support for the positions, past audit experience with similar situations, and the potential interest and penalties related to the matters. The Company maintains valuation allowances where it is more likely than not that all or a portion of a deferred tax asset will not be realized. Changes in valuation allowances are included in the tax provision in the period of change. In determining whether a valuation allowance is warranted, management evaluates factors such as prior earnings history, expected future earnings, carryback and carryforward periods and tax strategies that could potentially enhance the likelihood of the realization of a deferred tax asset. Additional disclosures regarding the Company's accounting for income taxes are provided in Note 17. Earnings per Share Basic earnings per share are computed by dividing income available to common stockholders by the weighted average number of common shares outstanding. Diluted earnings per share reflect the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock. In computing diluted earnings per share, only potential common shares that are dilutive (i.e., those that reduce earnings per share or increase loss per share) are included in the calculation. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions. These estimates or assumptions affect reported assets, liabilities, revenues and expenses as reflected in the consolidated financial statements. Actual results could differ from these estimates.