Stockholders' Equity Stock Repurchase Program (Details) (USD $)	1 Months Ended
Jan. 31, 2011 2011 Program [Member]	Mar. 31, 2014 2014 Program [Member]
Share Repurchase [Line Items]
Stock Repurchase Program, Authorized Amount	$ 400,000,000	$ 300,000,000

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