Loans (Loans Individually And Collectively Evaluated For Impairment) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment - Loans	$ 1,958	$ 3,423
Collectively Evaluated for Impairment - Loans	3,186,291	3,259,976
Total Loans	3,188,249	3,263,399
Individually Evaluated for Impairment - Allowance for Loan Losses	14	16
Collectively Evaluated for Impairment - Allowance for Loan Losses	29,275	30,822
Ending balance, allowance	29,289	30,838	$ 33,784	$ 30,057
Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment - Loans		22
Collectively Evaluated for Impairment - Loans	103,879	98,763
Total Loans	103,879	98,785
Collectively Evaluated for Impairment - Allowance for Loan Losses	1,493	1,158
Ending balance, allowance	1,493	1,158	1,441	1,408
Commercial Mortgages [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	1,401,289	1,281,295
Commercial Mortgages [Member] \| Multifamily Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Impairment - Loans	835,013	756,714
Total Loans	835,013	756,714
Collectively Evaluated for Impairment - Allowance for Loan Losses	7,151	5,851
Ending balance, allowance	7,151	5,851	6,423	6,119
Commercial Mortgages [Member] \| Other Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Impairment - Loans	447,484	433,330
Total Loans	447,484	433,330
Collectively Evaluated for Impairment - Allowance for Loan Losses	3,498	3,783
Ending balance, allowance	3,498	3,783	4,734	4,296
Commercial Mortgages [Member] \| Owner-occupied Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment - Loans	501	520
Collectively Evaluated for Impairment - Loans	118,291	90,731
Total Loans	118,792	91,251
Collectively Evaluated for Impairment - Allowance for Loan Losses	921	743
Ending balance, allowance	921	743	1,076	959
Residential Mortgages [Member] \| Closed-end [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment - Loans	1,189	1,814
Collectively Evaluated for Impairment - Loans	1,620,230	1,807,837
Total Loans	1,621,419	1,809,651
Individually Evaluated for Impairment - Allowance for Loan Losses	14	16
Collectively Evaluated for Impairment - Allowance for Loan Losses	15,684	18,828
Ending balance, allowance	15,698	18,844	19,347	15,740
Residential Mortgages [Member] \| Revolving Home Equity [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment - Loans		743
Collectively Evaluated for Impairment - Loans	59,231	66,967
Total Loans	59,231	67,710
Collectively Evaluated for Impairment - Allowance for Loan Losses	515	410
Ending balance, allowance	515	410	689	1,401
Consumer And Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment - Loans	268	324
Collectively Evaluated for Impairment - Loans	2,163	5,634
Total Loans	2,431	5,958
Collectively Evaluated for Impairment - Allowance for Loan Losses	13	49
Ending balance, allowance	$ 13	$ 49	$ 74	$ 134

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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