Income Tax (Income Tax Provision (Benefit) On Income From Operations) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Tax [Abstract]
Federal	$ 17,239	$ 13,552	$ 16,822
State	2,233	2,252	2,536
Current income tax expense benefit	19,472	15,804	19,358
Deferred	(2,916)	(959)	(1,730)
Income tax expense benefit	$ 16,556	$ 14,845	$ 17,628