Loans (Risk Ratings) (Details) - USD ($)		Jun. 30, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans		$ 3,152,461,000	$ 3,187,730,000
Deposit liabilities reclassified as loans receivable		269,000	519,000
Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			3,162,138,000
Watch [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			721,000
Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			22,622,000
Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			2,249,000
Commercial And Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020		9,769,000
2019		13,676,000
2018		10,602,000
2017		11,510,000
2016		7,619,000
Prior		26,873,000
Revolving Loans		24,624,000
Total Loans		104,673,000	103,879,000
Commercial And Industrial [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020		9,769,000
2019		13,228,000
2018		10,527,000
2017		11,374,000
2016		7,619,000
Prior		26,299,000
Revolving Loans		24,624,000
Total Loans		103,440,000	100,095,000
Commercial And Industrial [Member] | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2018		75,000
2017		136,000
Prior		347,000
Total Loans		558,000	3,493,000
Commercial And Industrial [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2019		448,000
Prior		227,000
Total Loans		675,000	291,000
SBA Paycheck Protection Program [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020		165,704,000
Total Loans		165,704,000
SBA Paycheck Protection Program [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020		165,704,000
Total Loans		165,704,000
Residential Mortgages [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020		1,778,000
2019		26,905,000
2018		331,093,000
2017		387,609,000
2016		278,075,000
Prior		444,721,000
Revolving Loans		58,945,000
Total Loans		1,529,126,000
Residential Mortgages [Member] | Closed-end [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans		1,470,181,000	1,621,419,000
Residential Mortgages [Member] | Revolving Home Equity [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans		58,945,000	59,231,000
Residential Mortgages [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020		1,778,000
2019		26,905,000
2018		330,632,000
2017		387,609,000
2016		278,075,000
Prior		442,091,000
Revolving Loans		57,886,000
Total Loans		1,524,976,000
Residential Mortgages [Member] | Pass [Member] | Closed-end [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			1,619,034,000
Residential Mortgages [Member] | Pass [Member] | Revolving Home Equity [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			58,816,000
Residential Mortgages [Member] | Watch [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Prior		302,000
Revolving Loans		415,000
Total Loans		717,000
Residential Mortgages [Member] | Watch [Member] | Closed-end [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			306,000
Residential Mortgages [Member] | Watch [Member] | Revolving Home Equity [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			415,000
Residential Mortgages [Member] | Special Mention [Member] | Closed-end [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			890,000
Residential Mortgages [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2018		461,000
Prior		2,328,000
Revolving Loans		644,000
Total Loans		3,433,000
Residential Mortgages [Member] | Substandard [Member] | Closed-end [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			1,189,000
Commercial Mortgages [Member] | Multifamily Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020		10,769,000
2019		154,913,000
2018		164,149,000
2017		164,406,000
2016		36,784,000
Prior		266,639,000
Total Loans		797,660,000	835,013,000
Commercial Mortgages [Member] | Other Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020		22,790,000
2019		43,346,000
2018		50,159,000
2017		56,721,000
2016		107,812,000
Prior		153,192,000
Total Loans		434,020,000	447,484,000
Commercial Mortgages [Member] | Owner-occupied Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020		4,825,000
2019		43,846,000
2018		9,118,000
2017		11,944,000
2016		12,712,000
Prior		37,417,000
Total Loans		119,862,000	118,792,000
Commercial Mortgages [Member] | Pass [Member] | Multifamily Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020		10,769,000
2019		154,913,000
2018		164,149,000
2017		163,104,000
2016		33,171,000
Prior		266,639,000
Total Loans		792,745,000	831,360,000
Commercial Mortgages [Member] | Pass [Member] | Other Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020		22,790,000
2019		43,346,000
2018		50,159,000
2017		56,721,000
2016		96,650,000
Prior		151,641,000
Total Loans		421,307,000	437,655,000
Commercial Mortgages [Member] | Pass [Member] | Owner-occupied Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020		4,825,000
2019		43,846,000
2018		9,118,000
2017		10,076,000
2016		12,712,000
Prior		36,813,000
Total Loans		117,390,000	113,534,000
Commercial Mortgages [Member] | Watch [Member] | Multifamily Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2017		1,302,000
2016		2,295,000
Total Loans		3,597,000
Commercial Mortgages [Member] | Watch [Member] | Other Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2016		9,775,000
Total Loans		9,775,000
Commercial Mortgages [Member] | Special Mention [Member] | Multifamily Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			3,653,000
Commercial Mortgages [Member] | Special Mention [Member] | Other Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			9,829,000
Commercial Mortgages [Member] | Special Mention [Member] | Owner-occupied Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans			4,757,000
Commercial Mortgages [Member] | Substandard [Member] | Multifamily Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2016		1,318,000
Total Loans		1,318,000
Commercial Mortgages [Member] | Substandard [Member] | Other Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2016		1,387,000
Prior		1,551,000
Total Loans		2,938,000
Commercial Mortgages [Member] | Substandard [Member] | Owner-occupied Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2017		1,868,000
Prior		604,000
Total Loans		2,472,000	501,000
Consumer And Other Excluding Overdrafts [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2019		466,000
2018		25,000
2017		34,000
2016		279,000
Prior		343,000
Total Loans		1,147,000
Consumer And Other Excluding Overdrafts [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2019		217,000
2018		25,000
2017		34,000
2016		279,000
Prior		343,000
Total Loans		898,000	1,644,000	[1]
Consumer And Other Excluding Overdrafts [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2019		249,000
Total Loans		249,000	268,000	[1]
Consumer And Other Excluding Overdrafts [Member] | Internal Investment Grade [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	[1]		$ 1,912,000
Consumer And Other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans		$ 1,416,000

[1] Deposit account overdrafts were $269,000 and $519,000 at June 30, 2020 and December 31, 2019, respectively. Overdrafts are not assigned a risk rating and are therefore excluded from consumer loans in the tables above.