Accumulated Other Comprehensive Income (Changes in AOCI by Component) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[1]	$ 20,811	$ 2,789	$ (6,295)	$ 5,621
Other comprehensive loss before reclassifications	[1]	(4,049)	10,126	23,229	7,881
Amounts reclassified from accumulated other comprehensive income (loss)	[1]	(257)	(89)	(429)	(676)
Net current-period other comprehensive income (loss)	[1]	(4,306)	10,037	22,800	7,205
Ending balance	[1]	16,505	12,826	16,505	12,826
Unrealized Gains and Losses on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[1]	27,280	4,819	386	7,462
Other comprehensive loss before reclassifications	[1]	(4,049)	10,126	23,229	8,161
Amounts reclassified from accumulated other comprehensive income (loss)	[1]	(364)	(151)	(748)	(829)
Net current-period other comprehensive income (loss)	[1]	(4,413)	9,975	22,481	7,332
Ending balance	[1]	22,867	14,794	22,867	14,794
Unrealized Gains and Losses on Pension Plan Liability [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[1]	(6,469)	(2,030)	(6,681)	(1,841)
Other comprehensive loss before reclassifications	[1]	0	0	0	(280)
Amounts reclassified from accumulated other comprehensive income (loss)	[1]	107	62	319	153
Net current-period other comprehensive income (loss)	[1]	107	62	319	(127)
Ending balance	[1]	$ (6,362)	$ (1,968)	$ (6,362)	$ (1,968)

[1] All amounts are net of tax. Amounts in parenthesis indicate debits.