Benefit Plans (Schedule of Amounts Expected to be Amortized from AOCI into Net Periodic Pension Cost During Next Fiscal Year) (Details) (Expected to be amortized in 2015, USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014
Qualified Pension Plan [Member}
Net actuarial gain (loss)	$ (47)
Net amount to be amortized in next fiscal year	(47)
Nonqualified Pension Plans [Member]
Net actuarial gain (loss)	(14)
Net amount to be amortized in next fiscal year	$ (14)