Stockholders' Equity (Number And Cost Of Common Stock Shares Repurchased) (Details) (USD $) In Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Stockholders' Equity [Abstract]
Common stock repurchased (in shares)	5,021	2,961
Common stock repurchased	$ 134,026	$ 76,753