Accumulated Other Comprehensive Loss (Components of AOCI) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (82,106)	[1]	$ (66,574)
Other comprehensive income before reclassifications	(875)		(1,993)
Amounts reclassified from accumulated other comprehensive income	3,076	[2]	2,151	[2]
Net current period other comprehensive income	2,201		158
Ending balance	(79,905)	[3]	(66,416)	[3]
Unrealized Loss on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(6,292)	[4]	(6,483)	[4]
Other comprehensive income before reclassifications	1	[4]	(218)	[4]
Amounts reclassified from accumulated other comprehensive income	492	[2],[4]	453	[2],[4]
Net current period other comprehensive income	493	[4]	235	[4]
Ending balance	(5,799)	[4]	(6,248)	[4]
Unrealized Gains on Investment Securities Available for Sale
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	20,517	[4]	16,115	[4]
Other comprehensive income before reclassifications	(876)	[4]	(1,775)	[4]
Amounts reclassified from accumulated other comprehensive income	(35)	[2],[4]	0	[4]
Net current period other comprehensive income	(911)	[4]	(1,775)	[4]
Ending balance	19,606	[4]	14,340	[4]
Defined Benefit Pension Items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(96,331)	[4]	(76,206)	[4]
Other comprehensive income before reclassifications	0	[4]	0	[4]
Amounts reclassified from accumulated other comprehensive income	2,619	[2],[4]	1,698	[2],[4]
Net current period other comprehensive income	2,619	[4]	1,698	[4]
Ending balance	$ (93,712)	[4]	$ (74,508)	[4]

[1] Derived from 2012 Annual Report on Form 10-K.

[2] Amounts in parentheses indicate debits to profit/loss.

[3] Unaudited

[4] All amounts are net of tax. Amounts in parentheses indicate debits.