Subsequent Events (Narrative) (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	1 Months Ended
Aug. 08, 2012 Repurchase Program Expiring August 31, 2015	Aug. 15, 2012 Repurchase Program Expiring November 30, 2013
Stock Repurchase Program, Authorized Amount	$ 750
Stock Repurchase Program, Expiration Date	Aug. 31, 2015	Nov. 30, 2013

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

No definition available.

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