Accumulated Other Comprehensive Income (Accumulated Comprehensive Income, net of income tax) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive (Loss) income, net of tax, Total	$ (8,047)	$ (10,963)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive (Loss) income, net of tax, Total	(8,047)	(10,963)
Accumulated Other Than Temporary Impairment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized gain on securities available-for-sale which are not other-than-temporarily impaired	(9,280)	(12,654)
Income tax effect of unrealized gain on securities available-for-sale	1,439	1,682
Net unrealized gain on securities available for sale wich are not other than temporarily impaired	(7,841)	(10,972)
Accumulated Net Gain Loss From Designated Or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized loss on cash flow hedges	(329)	14
Income tax effect of unrealized loss on cash flow hedges	123	(5)
Net unrealized (loss) income on cash flow hedges	$ (206)	$ 9

Accumulated unrealized gain (loss), after tax, on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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