Loans and Allowance for Credit Losses (Rollforward of TDRs) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Allowance for Credit Losses [Line Items]
TDR beginning balance	$ 11,781	$ 16,624
New TDRs	41
Disbursements (Payments)	(2,154)	(776)
Charge offs	(3)	(459)
Reclassifications/Transfer In/(Out)		(74)
Payoffs	(353)	(3,170)
TDR ending balance	9,312	12,145
TDR, Related Allowance	344	621
Impaired Nonaccrual Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
TDR beginning balance	3,118	3,298
Disbursements (Payments)	(1,391)	(86)
Charge offs	(3)	(80)
Reclassifications/Transfer In/(Out)		80
TDR ending balance	1,724	3,212
TDR, Related Allowance	137	376
Impaired Nonaccrual Loans [Member] | Residential Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Charge offs		(80)
Reclassifications/Transfer In/(Out)		80
Impaired Nonaccrual Loans [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
TDR beginning balance		83
Reclassifications/Transfer In/(Out)		(83)
Impaired Nonaccrual Loans [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
TDR beginning balance	320	337
Disbursements (Payments)	(12)	(13)
TDR ending balance	308	324
TDR, Related Allowance	4	20
Impaired Nonaccrual Loans [Member] | Construction Loans [Member] | Commercial and Residential Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
TDR beginning balance	2,798	2,878
Disbursements (Payments)	(1,379)	(73)
Charge offs	(3)
Reclassifications/Transfer In/(Out)		83
TDR ending balance	1,416	2,888
TDR, Related Allowance	133	356
Impaired Accruing Restructured Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
TDR beginning balance	8,663	13,326
New TDRs	41
Disbursements (Payments)	(763)	(690)
Charge offs		(379)
Reclassifications/Transfer In/(Out)		(154)
Payoffs	(353)	(3,170)
TDR ending balance	7,588	8,933
TDR, Related Allowance	207	245
Impaired Accruing Restructured Loans [Member] | Residential Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
TDR beginning balance	4,454	4,536
New TDRs	41
Disbursements (Payments)	(73)	(63)
Reclassifications/Transfer In/(Out)		542
Payoffs	(353)	(351)
TDR ending balance	4,069	4,664
TDR, Related Allowance	185	194
Impaired Accruing Restructured Loans [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
TDR beginning balance	4,158	4,818
Disbursements (Payments)	(682)	(402)
Payoffs		(219)
TDR ending balance	3,476	4,197
TDR, Related Allowance	22	32
Impaired Accruing Restructured Loans [Member] | Construction Loans [Member] | Commercial and Residential Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
TDR beginning balance	51	3,972
Disbursements (Payments)	(8)	(225)
Charge offs		(379)
Reclassifications/Transfer In/(Out)		(696)
Payoffs		(2,600)
TDR ending balance	$ 43	72
TDR, Related Allowance		$ 19