Percent of ownership interest in a business that is sold in a disposal transaction.

No definition available.

Name:	bdx_DisposalGroupIncludingDiscontinuedOperationPercentOfBusinessSold
Namespace Prefix:	bdx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Number Of Customer Accounted For Ten Percent Or More Of Revenue

+ References

No definition available.

+ Details

Name:	bdx_NumberOfCustomerAccountedForTenPercentOrMoreOfRevenue
Namespace Prefix:	bdx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721673-107760

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_SegmentReportingInformationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=bdx_RespiratorySolutionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_DisposalGroupClassificationAxis=us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember
Namespace Prefix:
Data Type:	na
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Period Type:

Segment Data - Additional Information (Detail) $ in Millions	12 Months Ended
	Sep. 30, 2017 customer segment	Sep. 30, 2016 USD ($) customer	Sep. 30, 2015 USD ($) customer	Oct. 03, 2016
Segment Reporting Information [Line Items]
Number of principal business segments (segments) \| segment	2
Number of customers accounted for 10% or more of revenues (customers) \| customer	0	0	0
Respiratory Solutions
Segment Reporting Information [Line Items]
Disposal Group, Including Discontinued Operation, Revenue \| $		$ 822	$ 417
Disposal Group, Held-for-sale, Not Discontinued Operations \| Respiratory Solutions
Segment Reporting Information [Line Items]
Disposal Group, Including Discontinued Operation, Percent Of Business Sold				50.10%