Subsequent Events (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	1 Months Ended
Feb. 27, 2013	May 21, 2013 Subsequent Event [Member]	Jun. 14, 2013 Subsequent Event [Member]
Subsequent Event [Line Items]
Authorized repurchase amount	$ 25.0	$ 50.0
Remaining authorized repurchase amount			$ 29.6

The remaining repurchase amount authorized by an entity's Board of Directors under a stock repurchase plan.

No definition available.

Name:	us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration