Stock Repurchase Programs (Details)	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Stock Repurchase Programs (Textual) [Abstract]
Vested shares included in treasury stock related to stock awards surrendered for withholding taxes	17,145	34,923
Remaining number of shares to be purchased under existing stock repurchase programs	50,123,550