Loans (Troubled Debt Restructurings on Financing Receivables) (Details) Unit13 in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($) loan
TDRs	$ 6,678	$ 6,705
Less: TDRs included in non-accrual loans	(26)	(29)
Accrual TDR loans	$ 6,652	$ 6,676
Number of TDR loans	13	13
Number of non-accrual TDR loans	(1)	(1)
Number of accrual TDR loans	12	12
Commercial Real Estate Portfolio Segment [Member]
TDRs	$ 5,590	$ 5,612
Number of TDR loans | loan	7	7
Residential First Mortgages Portfolio Segment [Member]
TDRs	$ 66	$ 66
Number of TDR loans | loan	1	1
Residential Rentals Portfolio Segment [Member]
TDRs	$ 215	$ 216
Number of TDR loans | loan	1	1
Construction And Land Development Portfolio Segment [Member]
TDRs	$ 729	$ 729
Number of TDR loans | loan	2	2
Commercial Portfolio Segment [Member]
TDRs		$ 53
Number of TDR loans | loan		1
Commercial Equipment Portfolio Segment [Member]
TDRs	$ 78	$ 29
Number of TDR loans | loan	2	1