Supplemental Comprehensive Income Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Supplemental Comprehensive Income Disclosures [Abstract]
Unrealized holding gains on securities arising during the period	$ (3,982)	$ 2,543
Reclassification adjustment for gains on securities included in net income	(2,840)	(652)
Total unrealized gains on securities	(6,822)	1,891
Unrealized holding losses on derivatives arising during the period	(130)	(516)
Unrealized holding gains on securities arising during the period	837	(890)
Reclassification adjustment for gains on derivatives included in net income, before Tax	0	78
Total unrealized gain on derivatives	(130)	(438)
Reclassification adjustment for gains on securities included in net income	596	228
Total other comprehensive (loss) income	(6,952)	1,453
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax	1,433	(662)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	27	181
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	0	(28)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax, Total	27	153
Other Comprehensive Income (Loss), Tax	1,460	(509)
Other comprehensive income (loss) before reclassification adjustment	(3,145)	1,653
Total unrealized (losses) gains on securities	(5,389)	1,229
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	(103)	(335)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	0	(50)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Total	(103)	(285)
Total other comprehensive (loss) income	(5,492)	944
Reclassification adjustment for gains on securities included in net income	$ 2,244	$ 424