Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Unrealized gains on investment securities, before tax [Abstract]
Unrealized holding gains arising during period, before tax		$ 3,562	$ 1,844
Less reclassification adjustment for gains realized in net income, before tax		367	187
Unrealized gains on investment securities, before tax		3,195	1,657
Unrecognized benefit obligation expense, before tax [Abstract]
Less reclassification adjustment for amortization, before tax		103	(17)
Unrecognized benefit obligation		(103)	(17)
Unrealized loss on derivative instrument, before tax		(488)	(280)
Other comprehensive income net, before tax		2,604	1,360
Unrealized gains on investment securities, tax [Abstract]
Unrealized holding gains arising during period, tax		1,229	749
Less reclassification adjustment for gains realized in net income, tax		125	64
Unrealized gains on investment securities, tax		1,104	685
Unrecognized benefit obligation expense, tax [Abstract]
Less reclassification adjustment for amortization, tax		0	0
Unrecognized benefit obligation, tax		0	0
Unrealized loss on derivative instrument, tax		(166)	(159)
Other comprehensive income net, tax		938	526
Unrealized gains on investment securities [Abstract]
Unrealized holding gains arising during period, net of tax		2,333	1,095
Less reclassification adjustment for gains realized in net income, net of tax	[1]	242	123
Unrealized gains (losses) on investment securities, net of tax		2,091	972
Unrecognized benefit obligation expense [Abstract]
Less reclassification adjustment for amortization, net of tax	[2]	(103)	(17)
Unrecognized benefit obligation expense		(103)	(17)
Unrealized loss on derivative instrument, net of tax		(322)	(121)
Other comprehensive income (loss)		1,666	$ 834
Unrecognized benefit obligation		(3,754)		$ (3,677)
Unrealized gains (losses) on AFS investments		2,189		124
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax		(688)		(366)
Accumulated other comprehensive loss		$ (2,253)		$ (3,919)

[1] Gross amounts are included in net gains on the sale of AFS investment securities on the Consolidated Statements of Income in total non-interest income, net of $125 thousand and $64 thousand in taxes. See Note 15. C

[2] Gross amounts are included in salaries and benefits on the Consolidated Statements of Income in non-interest expense.