Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ 1,531
Other comprehensive income (loss)	(149)	332
Ending balance	1,382	(436)
Available-for-Sale Securities Without Other-Than-Temporary Impairments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	9,451	7,202
Unrealized gains/losses arising during the period	(911)	425
Reclassifications from accumulated other comprehensive income	(16)	(591)
Other comprehensive income (loss)	(927)	(166)
Ending balance	8,524	7,036
Available-for-Sale Securities With Other-Than-Temporary Impairments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(2,162)	(2,318)
Unrealized gains/losses arising during the period	10	53
Reclassifications from accumulated other comprehensive income	0	0
Other comprehensive income (loss)	10	53
Ending balance	(2,152)	(2,265)
Cash Flow Hedge
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(2,484)	(1,834)
Unrealized gains/losses arising during the period	(69)	(40)
Reclassifications from accumulated other comprehensive income	157	146
Other comprehensive income (loss)	88	106
Ending balance	(2,396)	(1,728)
Defined Benefit Pension Plan
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(2,364)	(4,272)
Unrealized gains/losses arising during the period	0	0
Reclassifications from accumulated other comprehensive income	591	534
Other comprehensive income (loss)	591	534
Ending balance	$ (1,773)	$ (3,738)