Schedule of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Change in net unrealized Gain during period:
Change in net unrealized gain during period, before tax amount	$ (9,196)	$ 2,816	$ 1,412	$ 17,167
Change in net unrealized gain during period, tax expense (benefit)	(3,618)	1,108	555	6,755
Change in net unrealized gain during period, net of tax amount	(5,578)	1,708	857	10,412
Reclassification adjustment for gains included in net income:
Reclassification adjustment for gains included in net income, before tax amount	(46)	(17)	(52)	(88)
Reclassification adjustment for gains included in net income, tax expense (benefit)	(18)	(7)	(20)	(35)
Reclassification adjustment for gains included in net income, net of tax amount	(28)	(10)	(32)	(53)
Change in unamortized loss on available-for-sale securities transferred into held-to-maturity	451	0	902	0
Other Comprehensive Income (Loss), Transfers from Held-to-maturity to Available-for-Sale Securities, Tax	177	0	355	0
Change in unamortized loss on available-for-sale securities transferred into held-to-maturity	274	0	547	0
Change in net actuarial loss:
Change in net actuarial loss, before tax amount	13	35	28	70
Change in net actuarial loss, tax expense (benefit)	5	14	11	28
Change in net actuarial loss, net of tax amount	8	21	17	42
Other comprehensive income (loss):
Other comprehensive income (loss), before tax	(8,778)	2,834	2,290	17,149
Total other comprehensive income, tax expense (benefit)	(3,454)	1,115	901	6,748
Total other comprehensive income, net of tax amount	$ (5,324)	$ 1,719	$ 1,389	$ 10,401