Share-Based Compensation - Summary of Performance-Based Restricted Stock Units Outstanding Footnote (Detail) shares in Thousands	12 Months Ended
Sep. 30, 2017 shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Percentage of target payout on which performance-based restricted stock units are based	200.00%
Expected forfeited performance-based restricted stock units (shares)	79
Units in excess of the expected performance payout (shares)	573

Adjustment of units in excess of expected performance to the amount of performance-based restricted stock units that are expected to vest at the balance sheet date.

No definition available.

Name:	bdx_UnitsInExcessOfExpectedPerformancePayout
Namespace Prefix:	bdx_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration