Supplemental Comprehensive Income Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Supplemental Comprehensive Income Disclosures [Abstract]
Unrealized holding gains on securities arising during the period	$ (5,382)	$ 1,690	$ (8,704)	$ 5,935
Reclassification adjustment for gains on securities included in net income	0	(92)	(8,102)	(695)
Total unrealized gains on securities	(5,382)	1,598	(16,806)	5,240
Unrealized holding gains (losses) on derivatives arising during the period	198	(49)	165	(631)
Unrealized holding gains on securities arising during the period	1,130	(591)	1,828	(2,077)
Reclassification adjustment for gains on derivatives included in net income, before Tax	0	20	10	93
Total unrealized gain on derivatives	198	(29)	175	(538)
Reclassification adjustment for gains on securities included in net income	0	32	1,701	243
Total other comprehensive (loss) income	(5,184)	1,569	(16,631)	4,702
Other Comprehensive Income (Loss), Securities, Available-for-sale, Tax	1,130	(559)	3,529	(1,834)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	(42)	17	(35)	221
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	0	(7)	(3)	(33)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax, Total	(42)	10	(38)	188
Other Comprehensive Income (Loss), Tax	1,088	(549)	3,491	(1,646)
Other comprehensive income (loss) before reclassification adjustment	(4,252)	1,099	(6,876)	3,858
Total unrealized (losses) gains on securities	(4,252)	1,039	(13,277)	3,406
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	156	(32)	130	(410)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	0	(13)	(7)	(60)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Total	156	(19)	137	(350)
Total other comprehensive (loss) income	(4,096)	1,020	(13,140)	3,056
Reclassification adjustment for gains on securities included in net income	$ 0	$ 60	$ 6,401	$ 452

Supplemental Comprehensive Income Disclosures [Abstract]

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