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

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables 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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Loans (Loans Individually And Collectively Evaluated For Impairment) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment - Loans	$ 2,225		$ 3,423
Collectively Evaluated for Impairment - Loans	3,194,909		3,259,976
Total Loans	3,197,134		3,263,399
Individually Evaluated for Impairment - Allowance for Loan Losses	50		16
Collectively Evaluated for Impairment - Allowance for Loan Losses	29,806		30,822
Ending balance, allowance	29,856	$ 29,768	30,838	$ 33,551	$ 35,832	$ 33,784
Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment - Loans	73		22
Collectively Evaluated for Impairment - Loans	105,353		98,763
Total Loans	105,426		98,785
Individually Evaluated for Impairment - Allowance for Loan Losses	36
Collectively Evaluated for Impairment - Allowance for Loan Losses	1,333		1,158
Ending balance, allowance	1,369	1,201	1,158	1,152	1,298	1,441
Commercial Mortgages [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	1,351,918		1,281,295
Commercial Mortgages [Member] \| Multifamily Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Impairment - Loans	798,289		756,714
Total Loans	798,289		756,714
Collectively Evaluated for Impairment - Allowance for Loan Losses	6,819		5,851
Ending balance, allowance	6,819	6,730	5,851	6,497	7,048	6,423
Commercial Mortgages [Member] \| Other Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively Evaluated for Impairment - Loans	435,105		433,330
Total Loans	435,105		433,330
Collectively Evaluated for Impairment - Allowance for Loan Losses	3,389		3,783
Ending balance, allowance	3,389	3,440	3,783	4,196	4,768	4,734
Commercial Mortgages [Member] \| Owner-occupied Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment - Loans	506		520
Collectively Evaluated for Impairment - Loans	118,018		90,731
Total Loans	118,524		91,251
Collectively Evaluated for Impairment - Allowance for Loan Losses	1,058		743
Ending balance, allowance	1,058	828	743	826	911	1,076
Residential Mortgages [Member] \| Closed-end [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment - Loans	1,368		1,814
Collectively Evaluated for Impairment - Loans	1,673,171		1,807,837
Total Loans	1,674,539		1,809,651
Individually Evaluated for Impairment - Allowance for Loan Losses	14		16
Collectively Evaluated for Impairment - Allowance for Loan Losses	16,687		18,828
Ending balance, allowance	16,701	17,148	18,844	20,311	20,953	19,347
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	62,875		66,967
Total Loans	62,875		67,710
Collectively Evaluated for Impairment - Allowance for Loan Losses	506		410
Ending balance, allowance	506	397	410	507	775	689
Consumer And Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually Evaluated for Impairment - Loans	278		324
Collectively Evaluated for Impairment - Loans	2,098		5,634
Total Loans	2,376		5,958
Collectively Evaluated for Impairment - Allowance for Loan Losses	14		49
Ending balance, allowance	$ 14	$ 24	$ 49	$ 62	$ 79	$ 74