Derivative Instruments and Hedging Activities - Additional Information (Detail) lb in Millions	12 Months Ended
	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($) lb	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification of terminated interest rate swaps to interest expense within the next 12 months	$ 5,000,000
After-tax loss recognized in other comprehensive income (loss)	11,000,000	$ 16,000,000	$ 0
Gains or losses, related to hedge ineffectiveness	0	0	$ 0
Forward exchange contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	2,300,000,000	2,200,000,000
Interest rate swaps | Care Fusion Corporation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount				$ 2,300,000,000
Interest rate swaps | Cash Flow Hedges
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	500,000,000	0
Interest rate swaps | Cash Flow Hedges | Care Fusion Corporation
Derivative Instruments and Hedging Activities Disclosures [Line Items]
After-tax loss recognized in other comprehensive income (loss)		8,000,000
Fixed To Floating
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	$ 375,000,000	375,000,000
Interest rate	3.125%
Commodity forward contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	$ 0	$ 25,000,000
Notional amount, mass (lb) | lb		49
Commodity forward contracts | Cash Flow Hedges
Derivative Instruments and Hedging Activities Disclosures [Line Items]
After-tax loss recognized in other comprehensive income (loss)		$ 7,000,000