Accumulated Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			$ (17,605)	[1]	$ (323)
Other comprehensive income before reclassifications			8,032		(12,221)
Amounts reclassified from accumulated other comprehensive income			(466)		(2,140)
Other comprehensive income (loss), net of tax	(131)	570	7,566		(14,361)
Ending balance	(10,039)	(14,684)	(10,039)		(14,684)
Unrealized gains (losses) on available for sale securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(14,476)		3,650
Other comprehensive income before reclassifications			8,050		(12,221)
Amounts reclassified from accumulated other comprehensive income			(466)		(1,679)
Other comprehensive income (loss), net of tax			7,584		(13,900)
Ending balance	(6,892)	(10,250)	(6,892)		(10,250)
Interest rate swaps
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			0
Other comprehensive income before reclassifications			(18)
Amounts reclassified from accumulated other comprehensive income			0
Other comprehensive income (loss), net of tax			(18)
Ending balance	(18)		(18)
Defined benefit plan items [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(3,129)		(3,973)
Other comprehensive income before reclassifications			0		0
Amounts reclassified from accumulated other comprehensive income			0		(461)
Other comprehensive income (loss), net of tax			0		(461)
Ending balance	$ (3,129)	$ (4,434)	$ (3,129)		$ (4,434)

[1] Derived from audited consolidated financial statements