Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2014	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Defined Benefit Plan Disclosure [Line Items]
Assumed health care trend rate			6.60%	6.80%
Ultimate health care trend rate beginning in 2024			5.00%	5.00%
Percent of total assets domestic plans			66.00%
Amount recognized in Accumulated other comprehensive income before income taxes for net actuarial loss	$ 94		$ 94	$ 107
Accumulated other comprehensive income into post employment benefit cost			11
Charge associated with workforce reduction actions		$ 36
Cost of the savings incentive plan			61	54	$ 39
Employees contribution guaranteed by the company to the fixed income fund of the Savings Incentive Plan	256		256
Care Fusion Corporation
Defined Benefit Plan Disclosure [Line Items]
Change in workforce related costs			$ 40	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%
Foreign Plans
Defined Benefit Plan Disclosure [Line Items]
Net pension and postretirement cost			$ 35	32	25
Pension plan assets at fair value	624		624	575
Pension plan projected benefit obligations	$ 951		$ 951	780
Percent of total plan assets foreign plans	34.00%		34.00%
Foreign Plans | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	$ 228		$ 228	206
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Net pension and postretirement cost			113	93	74
Pension plan assets at fair value	1,855	1,829	1,855	1,732	1,829
Pension plan projected benefit obligations	2,719	2,366	2,719	2,426	2,366
Estimated net actuarial loss that will be amortized from accumulated other comprehensive income			(93)
Estimated prior service credit costs that will be amortized from accumulated other comprehensive income			14
Employer contribution			145	65
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net pension and postretirement cost			5	9	10
Pension plan projected benefit obligations	184	$ 201	184	186	$ 201
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	1,231		1,231	1,157
Employer contribution	100
U.S. Plans | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	$ 459		$ 459	$ 335