Shareholders' Equity (details) - Additional Repurchase Authorization (Subsequent Event [Member], USD $) In Billions, unless otherwise specified	0 Months Ended
Oct. 22, 2013
Subsequent Event [Member]
Subsequent Event
Additional share repurchase authorization	$ 5.0

Amount of a stock repurchase plan authorized by an entity's Board of Directors.

No definition available.

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