Fair Value Measurements (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jun. 30, 2014		Mar. 31, 2014
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Assets, Fair Value Disclosure, Recurring	$ 76		$ 55
Fair Value, Inputs, Level 2 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Assets, Fair Value Disclosure, Recurring	76		55
Level 3 Instruments [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Assets, Fair Value Disclosure, Recurring	0		0
Reconciliation of fair value activity for Level 3 derivative contracts
Balance as of March 31, 2012	(19)	[1]
Realized/unrealized gain included in earnings	4	[1],[2]
Settlements	(2)	[1]
Balance as of September 30, 2012	$ (17)	[1]

[1] Represents net derivative liabilities.

[2] Included in “Other expense (income), net.”