Loans Receivable and Allowance for Credit Losses (Loan Portfolio by Pass Rating) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	$ 175,123		$ 966,179
Fiscal Year Before Latest Fiscal Year	972,254		341,920
Two Years Before Latest Fiscal Year	337,003		292,806
Three Years Before Latest Fiscal Year	287,203		78,669
Four Years Before Latest Fiscal Year	77,197		376,336
Prior	1,101,905		758,958
Revolving Loans	314,568		725
Revolving Loans to Term Loans	718		266,825
Total	3,265,971		3,082,418
Prior, Gross charge-offs	1
Total, Gross charge-offs	1	$ 766
Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	2,602		56,893
Fiscal Year Before Latest Fiscal Year	54,989		40,644
Two Years Before Latest Fiscal Year	40,275		33,019
Three Years Before Latest Fiscal Year	32,801		12,959
Four Years Before Latest Fiscal Year	12,427		23,918
Prior	103,589		82,690
Total	246,683		250,123
Total, Gross charge-offs
Residential [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	2,602		56,893
Fiscal Year Before Latest Fiscal Year	54,989		40,465
Two Years Before Latest Fiscal Year	40,097		33,019
Three Years Before Latest Fiscal Year	32,801		12,959
Four Years Before Latest Fiscal Year	12,427		23,918
Prior	103,409		82,144
Total	246,325		249,398
Residential [Member] | Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Prior			303
Total			303
Residential [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fiscal Year Before Latest Fiscal Year			179
Two Years Before Latest Fiscal Year	178
Prior	180		243
Total	358		422
Commercial & Multi-Family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	165,350		854,898
Fiscal Year Before Latest Fiscal Year	849,606		234,441
Two Years Before Latest Fiscal Year	232,502		235,830
Three Years Before Latest Fiscal Year	228,676		55,752
Four Years Before Latest Fiscal Year	55,126		320,353
Prior	935,672		643,955
Total	2,466,932		2,345,229
Total, Gross charge-offs
Commercial & Multi-Family [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	165,350		854,299
Fiscal Year Before Latest Fiscal Year	849,009		234,441
Two Years Before Latest Fiscal Year	232,502		235,830
Three Years Before Latest Fiscal Year	228,676		55,752
Four Years Before Latest Fiscal Year	55,126		312,353
Prior	913,116		628,191
Total	2,443,779		2,320,866
Commercial & Multi-Family [Member] | Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Prior	13,039		14,183
Total	13,039		14,183
Commercial & Multi-Family [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year			599
Fiscal Year Before Latest Fiscal Year	597
Four Years Before Latest Fiscal Year			8,000
Prior	9,517		1,581
Total	10,114		10,180
Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	4,244		51,783
Fiscal Year Before Latest Fiscal Year	65,049		58,827
Two Years Before Latest Fiscal Year	58,553		17,518
Three Years Before Latest Fiscal Year	19,388
Four Years Before Latest Fiscal Year			4,974
Prior	9,097		4,031
Revolving Loans	6,222
Revolving Loans to Term Loans			7,798
Total	162,553		144,931
Total, Gross charge-offs
Construction [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	4,244		51,783
Fiscal Year Before Latest Fiscal Year	65,049		58,827
Two Years Before Latest Fiscal Year	58,553		17,518
Three Years Before Latest Fiscal Year	19,388
Four Years Before Latest Fiscal Year			1,794
Prior	5,880		4,031
Revolving Loans	6,222
Revolving Loans to Term Loans			7,798
Total	159,336		141,751
Construction [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Four Years Before Latest Fiscal Year			3,180
Prior	3,217
Total	3,217		3,180
Commercial Business [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	1,266		70
Fiscal Year Before Latest Fiscal Year	320		5,331
Two Years Before Latest Fiscal Year	3,040		5,470
Three Years Before Latest Fiscal Year	5,394		8,501
Four Years Before Latest Fiscal Year	8,223		25,626
Prior	46,036		21,845
Revolving Loans	263,319
Revolving Loans to Term Loans			215,164
Total	327,598		282,007
Total, Gross charge-offs	1	$ 766
Commercial Business [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	1,266		70
Fiscal Year Before Latest Fiscal Year	320		5,331
Two Years Before Latest Fiscal Year	3,040		5,470
Three Years Before Latest Fiscal Year	5,394		8,070
Four Years Before Latest Fiscal Year	7,813		22,940
Prior	41,161		19,487
Revolving Loans	259,567
Revolving Loans to Term Loans			212,402
Total	318,561		273,770
Commercial Business [Member] | Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Three Years Before Latest Fiscal Year			431
Four Years Before Latest Fiscal Year	410
Prior	1,562		1,600
Revolving Loans	3,382
Revolving Loans to Term Loans			2,385
Total	5,354		4,416
Commercial Business [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Four Years Before Latest Fiscal Year			2,686
Prior	3,313		758
Revolving Loans	370
Revolving Loans to Term Loans			377
Total	3,683		3,821
Home Equity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	1,034		1,541
Fiscal Year Before Latest Fiscal Year	1,757		643
Two Years Before Latest Fiscal Year	602		830
Three Years Before Latest Fiscal Year	815		1,390
Four Years Before Latest Fiscal Year	1,364		1,465
Prior	7,511		6,437
Revolving Loans	45,021		725
Revolving Loans to Term Loans	718		43,857
Total	58,822		56,888
Total, Gross charge-offs
Home Equity [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	1,034		1,541
Fiscal Year Before Latest Fiscal Year	1,757		643
Two Years Before Latest Fiscal Year	602		830
Three Years Before Latest Fiscal Year	815		1,390
Four Years Before Latest Fiscal Year	1,364		1,465
Prior	7,511		6,437
Revolving Loans	45,021		513
Revolving Loans to Term Loans	506		43,857
Total	58,610		56,676
Home Equity [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Revolving Loans			212
Revolving Loans to Term Loans	212
Total	212		212
Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	627		994
Fiscal Year Before Latest Fiscal Year	533		2,034
Two Years Before Latest Fiscal Year	2,031		139
Three Years Before Latest Fiscal Year	129		67
Four Years Before Latest Fiscal Year	57
Revolving Loans	6
Revolving Loans to Term Loans			6
Total	3,383		3,240
Total, Gross charge-offs
Consumer [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current Fiscal Year	627		994
Fiscal Year Before Latest Fiscal Year	533		2,034
Two Years Before Latest Fiscal Year	2,031		139
Three Years Before Latest Fiscal Year	129		67
Four Years Before Latest Fiscal Year	57
Revolving Loans	6
Revolving Loans to Term Loans			6
Total	$ 3,383		$ 3,240