Income Taxes (Schedule Of Components Of Provision For Income Taxes) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Abstract]
Provision for income taxes, Current Federal									$ 2,367	$ 10,054	$ 7,777
Provision for income taxes, Current Foreign									4,447	931	1,460
Provision for income taxes, Current State and Local									4,942	2,256	4,591
Provision for income taxes, Total Current									11,756	13,241	13,828
Provision for income taxes, Deferred Federal									11,368	3,115	2,160
Provision for income taxes, Deferred Foreign									(1,129)	(340)	2,999
Provision for income taxes, Deferred State and Local									729	161	692
Provision for income taxes, Total Deferred									10,968	2,936	5,851
Provision for income taxes, Total	$ 1,080	$ 11,144	$ 6,064	$ 4,436	$ 4,413	$ 8,476	$ (1,551)	$ 4,839	$ 22,724	$ 16,177	$ 19,679