Accumulated Other Comprehensive Income (Loss) (''AOCI'') (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
Changes in AOCI
Balance at the beginning of the period, net of taxes	$ (92)	$ (4,690)	$ (4,029)	$ 2,681
Other comprehensive income (loss) before reclassification, net of taxes	(691)	385	3,281	(7,006)
Amounts reclassified from other comprehensive income (loss), net of taxes	(29)	24	(64)	44
Other comprehensive income (loss)	(720)	409	3,217	(6,962)
Balance at the end of the period, net of taxes	(812)	(4,281)	(812)	(4,281)
Unrealized Gains (Losses) on Available-for-Sale Securities and I/O Strips
Changes in AOCI
Balance at the beginning of the period, net of taxes	3,533	494	(430)	7,887
Other comprehensive income (loss) before reclassification, net of taxes	(679)	391	3,313	(6,980)
Amounts reclassified from other comprehensive income (loss), net of taxes	(27)		(56)	(22)
Other comprehensive income (loss)	(706)	391	3,257	(7,002)
Balance at the end of the period, net of taxes	2,827	885	2,827	885
Unamortized Unrealized Gain on Available-for-Sale Securities Reclassified to Held-to-Maturity
Changes in AOCI
Balance at the beginning of the period, net of taxes	450	481	466	497
Amounts reclassified from other comprehensive income (loss), net of taxes	(8)	(8)	(24)	(24)
Other comprehensive income (loss)	(8)	(8)	(24)	(24)
Balance at the end of the period, net of taxes	442	473	442	473
Defined Benefit Pension Plan Items
Changes in AOCI
Balance at the beginning of the period, net of taxes	(4,075)	(5,665)	(4,065)	(5,703)
Other comprehensive income (loss) before reclassification, net of taxes	(12)	(6)	(32)	(26)
Amounts reclassified from other comprehensive income (loss), net of taxes	6	32	16	90
Other comprehensive income (loss)	(6)	26	(16)	64
Balance at the end of the period, net of taxes	$ (4,081)	$ (5,639)	$ (4,081)	$ (5,639)