Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Defined Benefit Plan Disclosure [Line Items]
Assumed health care trend rate			6.80%	7.00%
Ultimate health care trend rate beginning in 2024			4.00%	5.00%
Percent of total assets domestic plans			67.00%
Amount recognized in Accumulated other comprehensive income before income taxes for net actuarial loss	$ 107	$ 145	$ 107	$ 145
Accumulated other comprehensive income into post employment benefit cost			13
Charge associated with workforce reduction actions		36
Change in estimate workforce reduction liability			5
Change in workforce liability	4		4
Cost of the savings incentive plan			54	39	$ 36
Employees contribution guaranteed by the company to the fixed income fund of the Savings Incentive Plan	235		235
Care Fusion Corporation
Defined Benefit Plan Disclosure [Line Items]
Change in workforce related costs			$ 126
Fixed Income Funds
Defined Benefit Plan Disclosure [Line Items]
Company's Target allocation percentage for asset mix			35.00%
Diversified
Defined Benefit Plan Disclosure [Line Items]
Company's Target allocation percentage for asset mix			34.00%
Equity securities
Defined Benefit Plan Disclosure [Line Items]
Company's Target allocation percentage for asset mix			31.00%
Change in Assumptions for Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Change in accounting estimate, estimated amount of change in the next fiscal year	18		$ 18
Foreign Plans
Defined Benefit Plan Disclosure [Line Items]
Net pension and postretirement cost			32	25	33
Pension plan assets at fair value	575	574	575	574
Pension plan projected benefit obligations	$ 780	765	$ 780	765
Percent of total plan assets foreign plans	33.00%		33.00%
Foreign Plans | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	$ 206	237	$ 206	237
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Net pension and postretirement cost			93	74	123
Pension plan assets at fair value	1,732	1,829	1,732	1,829	1,785
Pension plan projected benefit obligations	2,426	2,366	2,426	2,366	2,076
Estimated net actuarial loss that will be amortized from accumulated other comprehensive income			(79)
Estimated prior service credit costs that will be amortized from accumulated other comprehensive income			15
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net pension and postretirement cost			9	10	19
Pension plan projected benefit obligations	186	201	186	201	$ 243
Estimated net actuarial loss that will be amortized from accumulated other comprehensive income			(2)
Estimated prior service credit costs that will be amortized from accumulated other comprehensive income			5
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	1,157	1,255	1,157	1,255
U.S. Plans | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	$ 335	$ 393	$ 335	$ 393
U.S. Plans | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, spot rate used in calculating service and interest cost components, discount rate	0.56%
U.S. Plans | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, spot rate used in calculating service and interest cost components, discount rate	4.87%