Schedule of Comprehensive Income (Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Change in net unrealized Gain during period:
Change in net unrealized gain during period, before tax amount	$ 1,794	$ 931	$ (39,547)	$ (175)
Change in net unrealized gain during period, tax expense (benefit)	706	366	(15,562)	(69)
Change in net unrealized gain during period, net of tax amount	1,088	565	(23,985)	(106)
Reclassification adjustment for gains included in net income:
Reclassification adjustment for gains included in net income, before tax amount	(30)	(66)	(26)	(295)
Reclassification adjustment for gains included in net income, tax expense (benefit)	(12)	(26)	(10)	(116)
Reclassification adjustment for gains included in net income, net of tax amount	(18)	(40)	(16)	(179)
Change in net actuarial loss:
Change in net actuarial loss, before tax amount	33	35	102	102
Change in net actuarial loss, tax expense (benefit)	13	14	40	40
Change in net actuarial loss, net of tax amount	20	21	62	62
Other comprehensive income (loss):
Other comprehensive income (loss), before tax	1,797	900	(39,471)	(368)
Total other comprehensive income, tax expense (benefit)	707	354	(15,532)	(145)
Total other comprehensive income, net of tax amount	$ 1,090	$ 546	$ (23,939)	$ (223)