Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015
Consolidated Statements of Comprehensive Income [Abstract]
Net income, before tax amount		$ 6,460	$ 2,959
Income tax expense		2,255	1,020
Net income		4,205	1,939
Other comprehensive income (loss)
Unrealized holding gains on securities arising during the period, before tax		152	62
Unrealized holding gains on securities arising during the period, tax		55	25
Unrealized holding gains on securities arising during the period, net		97	37
Less: reclassification adjustment for gains on securities included in net income, before tax		94
Less: reclassification adjustment for gains on securities included in net income, tax		33
Less: reclassification adjustment for gains on securities included in net income, net of tax		61
Total unrealized gains on securities available for sale, before tax		58	62
Total unrealized gains on securities available for sale, tax		22	25
Total unrealized gains on securities available for sale, net of tax		36	37
Adjustments related to defined benefit plan, Amortization of prior service cost, before tax		20
Adjustments related to defined benefit plan, Amortization of prior service cost, net of tax		20
Total adjustments related to defined benefit plan, before tax		20
Total adjustments related to defined benefit plan, net of tax		20
Unrealized holding loss on cash flow hedges arising during the period, before tax		(492)
Unrealized holding loss on cash flow hedges arising during the period, tax		(202)
Unrealized holding loss on cash flow hedges arising during the period, net of tax		(290)
Total unrealized loss on cash flow hedges, before tax		(492)
Total unrealized loss on cash flow hedges, tax		(202)
Total unrealized loss on cash flow hedges, net of tax		(290)
Total other comprehensive income, before tax		(414)	62
Total other comprehensive income, tax		(180)	25
Total other comprehensive income, net	[1]	(234)	37
Total comprehensive income, before tax		6,046	3,021
Total comprehensive income, tax		2,075	1,045
Total comprehensive income		$ 3,971	$ 1,976

[1] All amounts are net of tax.