Subsequent Events (Details) (Stock Repurchase Program [Member], USD $) In Millions, unless otherwise specified	1 Months Ended	0 Months Ended
Jan. 31, 2012	May 19, 2014 Subsequent Event [Member]
Subsequent Event [Line Items]
Stock repurchase program, Authorized amount	$ 1,500	$ 1,000
Stock repurchase program, Period in force (in years)		3 years

Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_StockRepurchaseProgramPeriodInForce1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration