Loans Receivable and Allowance for Credit Losses - Loans Receivable by Credit Quality Risk Rating Indicator- Current Year (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
2024	$ 722,857	$ 1,506,562
2023	2,235,925	1,910,013
2022	3,793,302	1,615,910
2021	2,760,797	1,181,963
2020	2,179,169	963,225
Prior to 2020	5,387,330	2,868,925
Revolving Loans	1,575,506	716,838
Revolving loans to term loans	110,183	119,462
Total Loans	18,765,069	10,882,898
Total classified and criticized
Financing Receivable, Credit Quality Indicator [Line Items]
2024	4,451	11,882
2023	5,386	27,934
2022	93,602	32,648
2021	96,339	40,155
2020	63,862	12,753
Prior to 2020	178,510	81,269
Revolving Loans	45,463	39,570
Revolving loans to term loans	3,898	1,285
Total Loans	491,511	247,496
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2024	412	450
2023	2,915	27,934
2022	32,823	12,386
2021	18,293	30,920
2020	37,234	10,710
Prior to 2020	103,214	58,155
Revolving Loans	21,198	28,011
Revolving loans to term loans	2,579	687
Total Loans	218,668	169,253
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2024	4,039	4,421
2023	2,471	0
2022	60,779	20,262
2021	78,046	9,235
2020	26,628	2,043
Prior to 2020	75,296	23,114
Revolving Loans	24,265	11,559
Revolving loans to term loans	1,319	598
Total Loans	272,843	71,232
Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	7,011
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	0	7,011
Loss
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	0	0
Pass/Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2024	718,406	1,494,680
2023	2,230,539	1,882,079
2022	3,699,700	1,583,262
2021	2,664,458	1,141,808
2020	2,115,307	950,472
Prior to 2020	5,208,820	2,787,656
Revolving Loans	1,530,043	677,268
Revolving loans to term loans	106,285	118,177
Total Loans	18,273,558	10,635,402
Mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
2024	417,798	1,110,754
2023	1,743,894	1,550,892
2022	2,950,042	1,249,793
2021	2,185,402	1,035,213
2020	1,820,445	802,978
Prior to 2020	4,261,108	2,257,828
Revolving Loans	130,013	101,809
Revolving loans to term loans	13,119	33,846
Total Loans	13,521,821	8,143,113
Mortgage loans \| Total classified and criticized
Financing Receivable, Credit Quality Indicator [Line Items]
2024	3,484	3,735
2023	4,526	10,926
2022	20,488	3,048
2021	27,134	28,511
2020	36,362	10,558
Prior to 2020	118,913	46,961
Revolving Loans	4,934	4,934
Revolving loans to term loans	0	0
Total Loans	215,841	108,673
Mortgage loans \| Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2024	412	0
2023	2,915	10,926
2022	12,781	3,048
2021	13,238	28,511
2020	35,984	10,558
Prior to 2020	69,127	35,306
Revolving Loans	4,500	4,500
Revolving loans to term loans	0	0
Total Loans	138,957	92,849
Mortgage loans \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2024	3,072	3,735
2023	1,611	0
2022	7,707	0
2021	13,896	0
2020	378	0
Prior to 2020	49,786	11,655
Revolving Loans	434	434
Revolving loans to term loans	0	0
Total Loans	76,884	15,824
Mortgage loans \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	0	0
Mortgage loans \| Loss
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	0	0
Mortgage loans \| Pass/Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2024	414,314	1,107,019
2023	1,739,368	1,539,966
2022	2,929,554	1,246,745
2021	2,158,268	1,006,702
2020	1,784,083	792,420
Prior to 2020	4,142,195	2,210,867
Revolving Loans	125,079	96,875
Revolving loans to term loans	13,119	33,846
Total Loans	13,305,980	8,034,440
Commercial loans
Financing Receivable, Credit Quality Indicator [Line Items]
2024	285,395	366,725
2023	442,423	333,023
2022	780,061	348,016
2021	532,595	143,291
2020	348,707	145,863
Prior to 2020	1,033,984	525,471
Revolving Loans	1,109,655	506,031
Revolving loans to term loans	84,412	72,201
Total Loans	4,617,232	2,440,621
Commercial loans \| Total classified and criticized
Financing Receivable, Credit Quality Indicator [Line Items]
2024	967	8,147
2023	860	17,008
2022	73,114	29,600
2021	69,196	11,644
2020	27,500	2,186
Prior to 2020	58,743	34,065
Revolving Loans	39,656	34,069
Revolving loans to term loans	3,846	1,195
Total Loans	273,882	137,914
Commercial loans \| Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	450
2023	0	17,008
2022	20,042	9,338
2021	5,055	2,409
2020	1,250	152
Prior to 2020	34,059	22,752
Revolving Loans	16,102	23,333
Revolving loans to term loans	2,560	687
Total Loans	79,068	76,129
Commercial loans \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2024	967	686
2023	860	0
2022	53,072	20,262
2021	64,141	9,235
2020	26,250	2,034
Prior to 2020	24,684	11,313
Revolving Loans	23,554	10,736
Revolving loans to term loans	1,286	508
Total Loans	194,814	54,774
Commercial loans \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	7,011
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	0	7,011
Commercial loans \| Loss
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	0	0
Commercial loans \| Pass/Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2024	284,428	358,578
2023	441,563	316,015
2022	706,947	318,416
2021	463,399	131,647
2020	321,207	143,677
Prior to 2020	975,241	491,406
Revolving Loans	1,069,999	471,962
Revolving loans to term loans	80,566	71,006
Total Loans	4,343,350	2,302,707
Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
2024	19,664	29,083
2023	49,608	26,098
2022	63,199	18,101
2021	42,800	3,459
2020	10,017	14,384
Prior to 2020	92,238	85,626
Revolving Loans	335,838	108,998
Revolving loans to term loans	12,652	13,415
Total Loans	626,016	299,164
Consumer loans \| Total classified and criticized
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	9	0
2020	0	9
Prior to 2020	854	243
Revolving Loans	873	567
Revolving loans to term loans	52	90
Total Loans	1,788	909
Consumer loans \| Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	28	97
Revolving Loans	596	178
Revolving loans to term loans	19	0
Total Loans	643	275
Consumer loans \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	9	0
2020	0	9
Prior to 2020	826	146
Revolving Loans	277	389
Revolving loans to term loans	33	90
Total Loans	1,145	634
Consumer loans \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	0	0
Consumer loans \| Loss
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	0	0
Consumer loans \| Pass/Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2024	19,664	29,083
2023	49,608	26,098
2022	63,199	18,101
2021	42,791	3,459
2020	10,017	14,375
Prior to 2020	91,384	85,383
Revolving Loans	334,965	108,431
Revolving loans to term loans	12,600	13,325
Total Loans	624,228	298,255
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
2024	220,655	629,191
2023	788,663	894,075
2022	1,535,253	680,512
2021	1,114,981	498,768
2020	964,831	481,529
Prior to 2020	2,591,346	1,200,402
Revolving Loans	110,477	95,694
Revolving loans to term loans	11,536	32,240
Total Loans	7,337,742	4,512,411
Commercial \| Total classified and criticized
Financing Receivable, Credit Quality Indicator [Line Items]
2024	3,072	482
2023	2,184	10,926
2022	20,141	3,048
2021	3,238	28,511
2020	35,431	10,558
Prior to 2020	91,167	34,197
Revolving Loans	4,934	4,934
Revolving loans to term loans	0	0
Total Loans	160,167	92,656
Commercial \| Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	2,184	10,926
2022	12,781	3,048
2021	3,238	28,511
2020	35,431	10,558
Prior to 2020	48,972	24,598
Revolving Loans	4,500	4,500
Revolving loans to term loans	0	0
Total Loans	107,106	82,141
Commercial \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2024	3,072	482
2023	0	0
2022	7,360	0
2021	0	0
2020	0	0
Prior to 2020	42,195	9,599
Revolving Loans	434	434
Revolving loans to term loans	0	0
Total Loans	53,061	10,515
Commercial \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	0	0
Commercial \| Loss
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	0	0
Commercial \| Pass/Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2024	217,583	628,709
2023	786,479	883,149
2022	1,515,112	677,464
2021	1,111,743	470,257
2020	929,400	470,971
Prior to 2020	2,500,179	1,166,205
Revolving Loans	105,543	90,760
Revolving loans to term loans	11,536	32,240
Total Loans	7,177,575	4,419,755
Commercial \| Mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	7,337,742	4,512,411
Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
2024	83,575	344,095
2023	411,186	172,244
2022	497,184	184,136
2021	519,236	271,878
2020	520,873	230,456
Prior to 2020	1,140,287	601,970
Revolving Loans	15,884	6,115
Revolving loans to term loans	1,583	1,606
Total Loans	3,189,808	1,812,500
Multi-family \| Total classified and criticized
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	3,253
2023	1,611	0
2022	0	0
2021	1,059	0
2020	553	0
Prior to 2020	24,113	9,500
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	27,336	12,753
Multi-family \| Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	553	0
Prior to 2020	19,105	9,500
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	19,658	9,500
Multi-family \| Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	3,253
2023	1,611	0
2022	0	0
2021	1,059	0
2020	0	0
Prior to 2020	5,008	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	7,678	3,253
Multi-family \| Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	0	0
Multi-family \| Loss
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	0	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	0	0
Multi-family \| Pass/Watch
Financing Receivable, Credit Quality Indicator [Line Items]
2024	83,575	340,842
2023	409,575	172,244
2022	497,184	184,136
2021	518,177	271,878
2020	520,320	230,456
Prior to 2020	1,116,174	592,470
Revolving Loans	15,884	6,115
Revolving loans to term loans	1,583	1,606
Total Loans	3,162,472	1,799,747
Multi-family \| Mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans	3,189,808	1,812,500
Construction
Financing Receivable, Credit Quality Indicator [Line Items]
2024	35,709	41,209
2023	187,663	342,890
2022	475,357	185,034
2021	203,055	68,603
2020	48,243	1,339
Prior to 2020	16,565	14,171
Revolving Loans	3,652	0
Revolving loans to term loans	0	0
Total Loans	970,244	653,246
Construction \| Total classified and criticized
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	21,698	0
2020	0	0
Prior to 2020	0	771
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	21,698	771
Construction \| Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2024	0	0
2023	0	0
2022	0	0
2021	10,000	0
2020	0	0
Prior to 2020	0	0
Revolving Loans	0	0
Revolving loans to term loans	0	0
Total Loans	10,000	0

Loans Receivable and Allowance for Credit Losses - Loans Receivable by Credit Quality Risk Rating Indicator- Current Year (Details) - USD ($)
$ in Thousands