Subsequent Events (Details) (Subsequent Event [Member], USD $)	0 Months Ended
Oct. 15, 2013
Subsequent Event [Member]
Subsequent Event [Line Items]
Stock repurchase program, authorized amount	$ 500,000,000
Stock repurchase program, period in force	18 months

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