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

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Loans (Loans Outstanding By Class Of Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	$ 3,123,301	$ 3,187,730
Individually Evaluated for Impairment - Loans		1,958
Collectively Evaluated for Impairment - Loans		3,186,291
Total Loans	3,123,301	3,188,249
Individually Evaluated for Impairment - Allowance for Loan Losses		14
Collectively Evaluated for Impairment - Allowance for Loan Losses		29,275
Ending balance, allowance	34,105	29,289	$ 30,199	$ 30,838
Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	126,073	103,879
Collectively Evaluated for Impairment - Loans		103,879
Total Loans	126,073	103,879
Collectively Evaluated for Impairment - Allowance for Loan Losses		1,493
Ending balance, allowance	1,931	1,493	1,047	1,158
Commercial Mortgages [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	1,376,257	1,401,289
Commercial Mortgages [Member] \| Multifamily Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	813,859	835,013
Collectively Evaluated for Impairment - Loans		835,013
Total Loans	813,859	835,013
Collectively Evaluated for Impairment - Allowance for Loan Losses		7,151
Ending balance, allowance	8,647	7,151	6,435	5,851
Commercial Mortgages [Member] \| Other Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	442,181	447,484
Collectively Evaluated for Impairment - Loans		447,484
Total Loans	442,181	447,484
Collectively Evaluated for Impairment - Allowance for Loan Losses		3,498
Ending balance, allowance	3,792	3,498	3,517	3,783
Commercial Mortgages [Member] \| Owner-occupied Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	120,217	118,792
Individually Evaluated for Impairment - Loans		501
Collectively Evaluated for Impairment - Loans		118,291
Total Loans	120,217	118,792
Collectively Evaluated for Impairment - Allowance for Loan Losses		921
Ending balance, allowance	1,782	921	685	743
Residential Mortgages [Member] \| Closed-end [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	1,558,401	1,621,419
Individually Evaluated for Impairment - Loans		1,189
Collectively Evaluated for Impairment - Loans		1,620,230
Total Loans	1,558,401	1,621,419
Individually Evaluated for Impairment - Allowance for Loan Losses		14
Collectively Evaluated for Impairment - Allowance for Loan Losses		15,684
Ending balance, allowance	17,459	15,698	18,071	18,844
Residential Mortgages [Member] \| Revolving Home Equity [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	60,296	59,231
Collectively Evaluated for Impairment - Loans		59,231
Total Loans	60,296	59,231
Collectively Evaluated for Impairment - Allowance for Loan Losses		515
Ending balance, allowance	487	515	402	410
Consumer And Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	2,274
Individually Evaluated for Impairment - Loans		268
Collectively Evaluated for Impairment - Loans		2,163
Total Loans	2,274	2,431
Collectively Evaluated for Impairment - Allowance for Loan Losses		13
Ending balance, allowance	$ 7	$ 13	$ 42	$ 49