Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2017
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying Consolidated Financial Statements and Notes to Consolidated Financial Statements of Becton, Dickinson and Company (the “Company”) have been prepared in accordance with U.S. generally accepted accounting principles. 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	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 Cash equivalents consist of all highly liquid investments with a maturity of three months or less at time of purchase.
Short-Term Investments	Short-Term Investments Short-term investments consist of time deposits with maturities greater than three months and less than one year when purchased.
Trade and Financing Receivables	Trade and Financing 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 uncollectible.
Inventories	Inventories Inventories are stated at the lower of first-in, first-out cost or market.
Property, Plant and Equipment	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 12 years for leasehold improvements.
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets The Company’s unamortized intangible assets include goodwill and in-process research and development assets which arise from acquisitions. The Company currently reviews all indefinite-lived assets, including 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, and components within an operating segment that have similar economic characteristics are aggregated. Potential impairment of goodwill is 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, 2017 indicated that all identified reporting units’ fair values exceeded their respective carrying values. The review for impairment of in-process research and development assets is performed by comparing the fair value of the technology or project assets, estimated using an income approach, with their carrying value. In-process research and development assets are considered indefinite-lived assets and are reviewed at least annually for impairment until projects are completed or abandoned. Certain trademarks that are considered to generate cash flows indefinitely are also considered to be indefinite-lived intangible assets and these assets are also reviewed at least annually for impairment. 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. 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	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	Revenue Recognition Revenue from product sales is typically recognized when all of the following criteria have been met: persuasive evidence of an arrangement exists; delivery has occurred or services have been rendered; product price is fixed or determinable; collection of the resulting receivable is reasonably assured. Certain sales arrangements contain multiple deliverables, including equipment and service deliverables, which requires the Company to determine the separate units of account. If the deliverable meets the criteria of a separate unit of accounting, the arrangement consideration is allocated to each element based upon its relative selling price. In determining the best evidence of selling price of a unit of account the Company utilizes vendor-specific objective evidence (“VSOE”), which is the price the Company charges when the deliverable is sold separately. When VSOE is not available, management uses relevant third-party evidence (“TPE”) of selling price, if available. When neither VSOE nor TPE of selling price exists, management uses its best estimate of selling price. Revenue allocated to equipment deliverables is recognized upon customer acceptance, which occurs after the transfer of title and risk of loss to the customer and the completion of installation or training services. When related training services are considered inconsequential, delivery is deemed to occur upon the transfer of title and risk of loss, at which time revenue and the costs associated with installation and training are recognized. For equipment lease revenue, transactions are evaluated and classified as either operating leases or sales-type leases. Lease income for products sold under sales-type leases is recognized as revenue upon the completion of installation activities in the amount of the present value of the minimum lease payments. The financing component of sales-type leases is recorded as revenue over the lease term. For products sold under operating leases, revenue is recognized at the contracted rate over the rental period, as defined within the customer agreement. For products sold and leased with embedded software, if software is considered not essential to the non-software elements of a product but is considered more than incidental to a product as a whole, the product’s software elements must be separated from its non-software elements under the requirements relating to multiple-element arrangements and accounted for under software industry-specific revenue recognition requirements. However, if it is determined that the embedded software is more than incidental to the product as a whole but the non-software elements and software elements work together to deliver the essential functionality of the products as a whole, then the accounting for such product does not fall within the scope of software industry-specific accounting requirements. The Company’s domestic businesses sell products primarily to distributors that resell the products to end-user customers. Rebates are provided to distributors that sell to end-user customers at prices determined under a contract between the Company and the end-user customer. Provisions for rebates, as well as sales discounts and returns, are based upon estimates and are accounted for as a reduction of revenues when revenue is recognized.
Shipping and Handling Costs	Shipping and Handling Costs Shipping and handling costs are included in Selling and administrative expense.
Derivative Financial Instruments	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.
Income Taxes	Income Taxes United States income taxes are not provided on undistributed earnings of foreign subsidiaries where such undistributed earnings are indefinitely reinvested outside the United States. Deferred taxes are provided for earnings of foreign subsidiaries when those earnings are not considered indefinitely reinvested. Income taxes are provided and tax credits are recognized based on tax laws enacted at the dates of the financial statements. 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.
Earnings per Share	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	Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles 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.
New Accounting Principle Adopted and New Accounting Principles Not Yet Adopted	New Accounting Principle Adopted On October 1, 2016, the Company prospectively adopted amended requirements issued by the Financial Accounting Standards Board ("FASB") relating to the timing of recognition and classification of share-based compensation award-related income tax effects. Upon the settlement of awards during fiscal year 2017, the Company recorded tax benefits for the year ended of $77 million to Income tax provision (benefit) within its consolidated statement of income. These tax benefits were recorded within Capital in excess of par value on the Company's consolidated balance sheet in the prior-year period. Because these excess tax benefits are no longer recorded in Capital in excess of par value, the current period adjustment for the dilutive impact of share equivalents from share-based plans, which is used in the Company's computation of diluted earnings per share, increased by approximately 1 million shares. Also per the amended guidance, the Company classified the $77 million of excess tax benefits for the year ended September 30, 2017 on its consolidated statement of cash flows within Net Cash Provided by Operating Activities, rather than Net Cash Provided by (Used for) Financing Activities, which included the excess tax benefits for the years ended September 30, 2016 and 2015. The amended guidance allows entities to account for award forfeitures as they occur; however, the Company has elected to continue its determination of compensation cost recognized in each period based upon an estimate of expected future forfeitures. New Accounting Principles Not Yet Adopted In February 2016, the FASB issued a new lease accounting standard which requires lessees to recognize lease assets and lease liabilities on the balance sheet. The new standard also requires expanded disclosures regarding leasing arrangements. The Company is currently evaluating the impact that this new lease accounting standard will have on its consolidated financial statements upon its adoption of the standard on October 1, 2019. In May 2014, the FASB issued a new revenue recognition standard. Under this standard, revenue will be recognized upon the transfer of goods or services to customers and the amount of revenue recognized will reflect the consideration to which a reporting entity expects to be entitled in exchange for those goods or services. The Company intends to adopt the standard, as required, on October 1, 2018 and recently completed an initial assessment to identify the potential areas of impact that this new revenue recognition standard will have on its consolidated financial statements. As part of the initial assessment, the Company reviewed a representative sample of its contracts across its various businesses and geographies to identify potential differences that could result from applying the requirements of the new standard. The analysis included identifying whether there may be differences in timing of revenue recognition under the new standard as well as assessing performance obligations, variable consideration, and contract costs. The Company has not yet estimated the impact of the new standard on the timing and pattern of its revenue recognition. The Company continues to evaluate the available adoption methods, and apprises its audit committee of the project status regularly.
Contingencies	Contingencies Given the uncertain nature of litigation generally, the Company is not able, in all cases, to estimate the amount or range of loss that could result from an unfavorable outcome of the litigation to which the Company is a party. In accordance with U.S. generally accepted accounting principles, the Company establishes accruals to the extent probable future losses are estimable (in the case of environmental matters, without considering possible third-party recoveries). In view of the uncertainties discussed below, the Company could incur charges in excess of any currently established accruals and, to the extent available, liability insurance. In the opinion of management, any such future charges, individually or in the aggregate, could have a material adverse effect on the Company’s consolidated results of operations and consolidated cash flows. In June 2007, Retractable Technologies, Inc. (“RTI”) filed a complaint against the Company under the caption Retractable Technologies, Inc. vs. Becton Dickinson and Company (Civil Action No. 2:07-cv-250, U.S. District Court, Eastern District of Texas) alleging that the BD Integra™ syringes infringe patents licensed exclusively to RTI. In its complaint, RTI also alleged that the Company engaged in false advertising with respect to certain of the Company’s safety-engineered products in violation of the Lanham Act; acted to exclude RTI from various product markets and to maintain its market share through, among other things, exclusionary contracts in violation of state and federal antitrust laws; and engaged in unfair competition. In January 2008, the Court severed the patent and non-patent claims into separate cases, and stayed the non-patent claims during the pendency of the patent claims at the trial court level. On April 1, 2008, RTI filed a complaint against BD under the caption Retractable Technologies, Inc. and Thomas J. Shaw v. Becton Dickinson and Company (Civil Action No. 2:08-cv-141, U.S. District Court, Eastern District of Texas) alleging that the BD Integra™ syringes infringe another patent licensed exclusively to RTI. On August 29, 2008, the Court ordered the consolidation of the patent cases. RTI was subsequently awarded $5 million in damages at a jury trial with respect to the patent claims, which has been paid, and the patent cases are now concluded. On September 19, 2013, a jury returned a verdict against BD with respect to RTI’s Lanham Act claim and claim for attempted monopolization based on deception in the safety syringe market. The jury awarded RTI $113.5 million for its attempted monopolization claim (which would be trebled under the antitrust statute). The jury’s verdict rejected RTI’s monopolization claims in the markets for safety syringes, conventional syringes and safety IV catheters; its attempted monopolization claims in the markets for conventional syringes and safety IV catheters; and its claims for contractual restraint of trade and exclusive dealing in the markets for safety syringes, conventional syringes and safety IV catheters. In connection with the verdict, the Company recorded a pre-tax charge of approximately $341 million in the fourth quarter of fiscal year 2013. With respect to RTI's requested injunction relief, in November 2014, the Court granted RTI’s request that BD be ordered to issue certain corrective statements regarding its advertising and enjoined from making certain advertising claims. The Court denied RTI’s request for injunctive relief relating to BD’s contracting practices and BD’s safety syringe advertising, finding that RTI failed to prove that BD’s contracting practices violated the antitrust laws or that BD’s safety syringe advertising is false. On January 14, 2015, the Court granted in part and denied in part BD’s motion for a stay of the injunction. The Court held that, pending appeal, BD would not be required to send the corrective advertising notices to end-user customers, but only to employees, distributors and Group Purchasing Organizations. On January 15, 2015, the Court entered its Final Judgment in the case ordering that RTI recover $341 million for its attempted monopolization claim and $12 million for attorneys’ fees, and awarded pre and post-judgment interest and costs. On February 3, 2015, the Court of Appeals for the Fifth Circuit denied BD’s motion for a stay of the injunction pending the final appeal, and BD thereafter complied with the Court’s order. On April 23, 2015, the Court granted BD’s motion to eliminate the award of pre-judgment interest, and entered a new Final Judgment. BD thereafter appealed to the Court of Appeals challenging the entirety of the Final Judgment. On December 2, 2016, the Court of Appeals issued an opinion reversing the judgment as to RTI’s attempted monopolization claim and rendered judgment on that claim in favor of BD. As a result, the Company reversed $336 million of reserves associated with this judgment, which was recorded in Other operating (income) expense, net. The Court of Appeals affirmed the judgment for Lanham Act liability, and remanded the case to the district court to consider whether and if so how much profit should be disgorged by BD on that claim. The Court of Appeals vacated and remanded the injunction ordered by the Court. On January 31, 2017, RTI filed a petition for a writ of certiorari with the U.S. Supreme Court. On March 20, 2017, the U.S. Supreme Court denied certiorari, and the district court thereafter heard RTI’s request for disgorgement. On August 17, 2017, the district court entered judgment in favor of BD and ruled that RTI is not entitled to any award of money damages. RTI has appealed this ruling to the Fifth Circuit Court of Appeals. On July 17, 2015, a class action complaint was filed against the Company in the U.S. District Court for the Southern District of Georgia. The plaintiffs, Glynn-Brunswick Hospital Authority, trading as Southeast Georgia Health System, and Southeast Georgia Health System, Inc., seek to represent a class of acute care purchasers of BD syringes and IV catheters. The complaint alleges that BD monopolized the markets for syringes and IV catheters through contracts, theft of technology, false advertising, acquisitions, and other conduct. The complaint seeks treble damages but does not specify the amount of alleged damages. The Company filed a motion to dismiss the complaint which was granted on January 29, 2016. On September 23, 2016, the court denied plaintiffs’ motion to alter or amend the judgment to allow plaintiffs to file an amended complaint, and plaintiffs appealed that decision to the Eleventh Circuit Court of Appeals. The plaintiffs thereafter voluntarily dismissed their appeal, and the Court of Appeals dismissed the case on November 21, 2016. The Company is also involved both as a plaintiff and a defendant in other legal proceedings and claims that arise in the ordinary course of business. The Company believes that it has meritorious defenses to the suits pending against the Company and is engaged in a vigorous defense of each of these matters. The Company is a potentially responsible party to a number of federal administrative proceedings in the United States brought under the Comprehensive Environment Response, Compensation and Liability Act, also known as “Superfund,” and similar state laws. The affected sites are in varying stages of development. In some instances, the remedy has been completed, while in others, environmental studies are underway or commencing. For several sites, there are other potentially responsible parties that may be jointly or severally liable to pay all or part of cleanup costs.
Fair Value of Financial Instruments	The Company measures the fair value of forward exchange contracts and interest rate swaps based upon the present value of expected future cash flows using market-based observable inputs including credit risk, interest rate yield curves, foreign currency spot prices and forward prices. Long-term debt is recorded at amortized cost. The fair value of long-term debt is measured based upon quoted prices in active markets for similar instruments, which are considered Level 2 inputs in the fair value hierarchy. The fair value of long-term debt was $19.2 billion and $11.3 billion at September 30, 2017 and 2016, respectively. The fair value of the current portion of long-term debt was $206 million and $798 million at September 30, 2017 and 2016, respectively. The contingent consideration liabilities were recognized as part of the consideration transferred by the Company for certain acquisitions. The fair values of the contingent consideration liabilities were estimated using probability-weighted discounted cash flow models that were based upon the probabilities assigned with regard to achievement of the contingent events. The estimated fair values of the contingent consideration liabilities are remeasured each reporting period based upon increases or decreases in the probability of the contingent payments. The decrease to the total contingent consideration liability in fiscal year 2017 is primarily attributable to a $40 million payment of a contingent consideration liability recorded in connection with a previously closed acquisition. The Company’s policy is to recognize any transfers into fair value measurement hierarchy levels and transfers out of levels at the beginning of each reporting period.
Concentration of Credit Risk	Concentration of Credit Risk The Company maintains cash deposits in excess of government-provided insurance limits. Such cash deposits are exposed to loss in the event of nonperformance by financial institutions. Substantially all of the Company’s trade receivables are due from public and private entities involved in the healthcare industry. Due to the large size and diversity of the Company’s customer base, concentrations of credit risk with respect to trade receivables are limited. The Company does not normally require collateral. The Company is exposed to credit loss in the event of nonperformance by financial institutions with which it conducts business. However, this loss is limited to the amounts, if any, by which the obligations of the counterparty to the financial instrument contract exceed the obligations of the Company. The Company also minimizes exposure to credit risk by dealing with a diversified group of major financial institutions. The Company continually evaluates its accounts receivables for potential collection risks particularly those resulting from sales to government-owned or government-supported healthcare facilities in certain countries as payment may be dependent upon the financial stability and creditworthiness of those countries’ national economies. The Company continually evaluates all governmental receivables for potential collection risks associated with the availability of government funding and reimbursement practices. The Company believes the current reserves related to all governmental receivables are adequate and that this concentration of credit risk will not have a material adverse impact on its financial position or liquidity.