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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No definition available.

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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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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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Amount, before allowance for credit loss, of financing receivable.

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Loans (Loans Outstanding By Class Of Loans) (Details) - USD ($)	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	$ 3,152,461,000		$ 3,187,730,000
Individually Evaluated			1,958,000
Collectively Evaluated			3,186,291,000
Total Loans	3,152,461,000		3,188,249,000
Individually Evaluated - Allowance for Loan Losses			14,000
Collectively Evaluated - Allowance for Loan Losses			29,275,000
Ending balance, allowance	34,051,000	$ 34,105,000	29,289,000	$ 29,768,000	$ 30,199,000	$ 30,838,000
Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	104,673,000		103,879,000
Collectively Evaluated			103,879,000
Total Loans	104,673,000		103,879,000
Collectively Evaluated - Allowance for Loan Losses			1,493,000
Ending balance, allowance	1,593,000	1,931,000	1,493,000	1,201,000	1,047,000	1,158,000
SBA Paycheck Protection Program [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	165,704,000
Total Loans	165,704,000
Ending balance, allowance	249,000
Commercial Mortgages [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Total Loans	1,351,542,000		1,401,289,000
Commercial Mortgages [Member] \| Multifamily Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	797,660,000		835,013,000
Collectively Evaluated			835,013,000
Total Loans	797,660,000		835,013,000
Collectively Evaluated - Allowance for Loan Losses			7,151,000
Ending balance, allowance	8,856,000	8,647,000	7,151,000	6,730,000	6,435,000	5,851,000
Commercial Mortgages [Member] \| Other Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	434,020,000		447,484,000
Collectively Evaluated			447,484,000
Total Loans	434,020,000		447,484,000
Collectively Evaluated - Allowance for Loan Losses			3,498,000
Ending balance, allowance	3,860,000	3,792,000	3,498,000	3,440,000	3,517,000	3,783,000
Commercial Mortgages [Member] \| Owner-occupied Loan [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	119,862,000		118,792,000
Individually Evaluated			501,000
Collectively Evaluated			118,291,000
Total Loans	119,862,000		118,792,000
Collectively Evaluated - Allowance for Loan Losses			921,000
Ending balance, allowance	1,622,000	1,782,000	921,000	828,000	685,000	743,000
Residential Mortgages [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	1,529,126,000
Residential Mortgages [Member] \| Closed-end [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	1,470,181,000		1,621,419,000
Individually Evaluated			1,189,000
Collectively Evaluated			1,620,230,000
Total Loans	1,470,181,000		1,621,419,000
Individually Evaluated - Allowance for Loan Losses			14,000
Collectively Evaluated - Allowance for Loan Losses			15,684,000
Ending balance, allowance	17,384,000	17,459,000	15,698,000	17,148,000	18,071,000	18,844,000
Residential Mortgages [Member] \| Revolving Home Equity [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	58,945,000		59,231,000
Collectively Evaluated			59,231,000
Total Loans	58,945,000		59,231,000
Collectively Evaluated - Allowance for Loan Losses			515,000
Ending balance, allowance	482,000	487,000	515,000	397,000	402,000	410,000
Consumer And Other [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans outstanding	1,416,000
Individually Evaluated			268,000
Collectively Evaluated			2,163,000
Total Loans	1,416,000		2,431,000
Collectively Evaluated - Allowance for Loan Losses			13,000
Ending balance, allowance	$ 5,000	$ 7,000	$ 13,000	$ 24,000	$ 42,000	$ 49,000