Other Comprehensive Income (Loss) (Other Comprehensive Income (Loss) Components And Related Taxes) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Other Comprehensive Income (Loss) [Abstract]
Change in pension plan assets and benefit obligations, Before-tax amount	$ 634
Change in pension plan assets and benefit obligations, Tax effect	222
Change in pension plan assets and benefit obligations, Net-of-tax amount	412
Unrealized gains (losses) on available-for-sale securities, Before-tax amount	(3,390)	(3,166)
Unrealized gains (losses) on available-for-sale securities, Tax effect	(1,188)	(1,108)
Unrealized gains (losses) on available-for-sale securities, Net-of-tax amount	(2,202)	(2,058)
Reclassification adjustment for gains realized in net income, Before-tax amount		(6,635)
Reclassification adjustment for gains realized in net income, Tax effect		(2,322)
Reclassification adjustment for gains realized in net income, Net-of-tax amount		(4,313)
Unrealized net holding gain (loss) on cash flow hedge, Before-tax amount	173	204
Unrealized net holding gain (loss) on cash flow hedge, Tax effect	60	71
Unrealized net holding gain (loss) on cash flow hedge, Net-of-tax amount	113	133
Other comprehensive income (loss), Before-tax amount	(2,583)	(9,597)
Other comprehensive income (loss), Tax effect	(906)	(3,359)
Other comprehensive loss	$ (1,677)	$ (6,238)