Allowance For Loan Losses - Troubled Debt Restructures (Details)	3 Months Ended
	Mar. 31, 2020 USD ($) restructuring	Mar. 31, 2019 USD ($) restructuring	Dec. 31, 2019 USD ($)
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total Troubled Debt Restructure (TDR) loans	$ 18,100,000		$ 21,100,000
TDR loans on accrual status	12,200,000		17,100,000
TDR loans included in non-performing loans	$ 5,900,000		$ 4,000,000
Number of restructurings | restructuring	6	7
Pre-modification outstanding recorded investment	$ 3,915,000	$ 930,000
Post-modification recorded investment	3,697,000	921,000
Charge-offs associated with new TDRs	$ 0	$ 0
Number of TDRs that defaulted | restructuring	6	2
Post-modification outstanding recorded investment, TDRs that defaulted	$ 2,070,000	$ 174,000
Specific reserves allocated to TDRs	$ 1,275,000	$ 91,000
Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of restructurings | restructuring	0	1
Pre-modification outstanding recorded investment	$ 0	$ 421,000
Post-modification recorded investment	$ 0	$ 415,000
Number of TDRs that defaulted | restructuring	1	0
Post-modification outstanding recorded investment, TDRs that defaulted	$ 218,000	$ 0
Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of restructurings | restructuring	1	5
Pre-modification outstanding recorded investment	$ 474,000	$ 194,000
Post-modification recorded investment	$ 409,000	$ 192,000
Number of TDRs that defaulted | restructuring	1	2
Post-modification outstanding recorded investment, TDRs that defaulted	$ 151,000	$ 174,000
Commercial construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of restructurings | restructuring	4	0
Pre-modification outstanding recorded investment	$ 3,440,000	$ 0
Post-modification recorded investment	$ 3,287,000	$ 0
Number of TDRs that defaulted | restructuring	2	0
Post-modification outstanding recorded investment, TDRs that defaulted	$ 1,697,000	$ 0
Residential mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of restructurings | restructuring	0	1
Pre-modification outstanding recorded investment	$ 0	$ 315,000
Post-modification recorded investment	$ 0	$ 314,000
Number of TDRs that defaulted | restructuring	0	0
Post-modification outstanding recorded investment, TDRs that defaulted	$ 0	$ 0
Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of restructurings | restructuring	0	0
Pre-modification outstanding recorded investment	$ 0	$ 0
Post-modification recorded investment	$ 0	$ 0
Number of TDRs that defaulted | restructuring	0	0
Post-modification outstanding recorded investment, TDRs that defaulted	$ 0	$ 0
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of restructurings | restructuring	1	0
Pre-modification outstanding recorded investment	$ 1,000	$ 0
Post-modification recorded investment	$ 1,000	$ 0
Number of TDRs that defaulted | restructuring	2	0
Post-modification outstanding recorded investment, TDRs that defaulted	$ 4,000	$ 0
Extended Maturity Date
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of restructurings | restructuring	2	0
Post-modification recorded investment	$ 1,697,000	$ 0
Temporary payment reduction and payment re-amortization of remaining principal over extended term
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of restructurings | restructuring	2	6
Post-modification recorded investment	$ 978,000	$ 607,000
Forbearance of post default rights
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of restructurings | restructuring	2	0
Post-modification recorded investment	$ 1,022,000	$ 0
Other payment concessions
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of restructurings | restructuring	0	1
Post-modification recorded investment	$ 0	$ 314,000