Loans Receivable and Allowance for Credit Losses - Schedule Of Loans Held-For-Investment By Loan Portfolio Segments, Internal Risk Ratings, Gross Write-Offs And Vintage Year (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	$ 2,118,448		$ 7,211,782
Year 2	6,934,902		7,563,807
Year 3	7,171,840		9,549,557
Year 4	9,211,024		5,603,650
Year 5	5,417,461		3,663,285
Prior	10,592,826		7,419,863
Revolving Loans	12,603,470		12,520,741
Revolving Loans Converted to Term Loans	202,763		193,952
Total	54,252,734		53,726,637
Gross write-offs Total	16,983	$ 24,684
Pass
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	2,117,505		7,127,517
Year 2	6,837,678		7,422,477
Year 3	6,997,030		9,316,206
Year 4	8,965,414		5,414,088
Year 5	5,233,889		3,567,683
Prior	10,232,750		7,175,711
Revolving Loans	12,441,592		12,356,727
Revolving Loans Converted to Term Loans	181,862		173,075
Total	53,007,720		52,553,484
Pass | Federal Housing Administration Loan
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Nonaccrual loans	1,000		1,000
Criticized (accrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	659		74,566
Year 2	81,170		99,381
Year 3	134,949		197,313
Year 4	216,662		176,822
Year 5	164,961		87,799
Prior	316,613		209,605
Revolving Loans	161,714		154,085
Revolving Loans Converted to Term Loans	15,904		15,365
Total	1,092,632		1,014,936
Criticized (nonaccrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	284		9,699
Year 2	16,054		41,949
Year 3	39,861		36,038
Year 4	28,948		12,740
Year 5	18,611		7,803
Prior	43,463		34,547
Revolving Loans	164		9,929
Revolving Loans Converted to Term Loans	4,997		5,512
Total	152,382		158,217
Gross write-offs
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Gross write-offs year 1	0		29
Gross write-offs year 2	9		50,973
Gross write-offs year 3	0		17,137
Gross write-offs year 4	46		11,119
Gross write-offs year 5	437		1,568
Gross write-offs year Prior	14,175		3,025
Gross write-offs year Revolving Loans	0		27,989
Gross write-offs Revolving Loans Converted to Term Loans	0		5
Gross write-offs Total	14,667		111,845
Consumer Loan
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Converted to term loan		15,000
Commercial lending
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	1,409,421		4,817,251
Year 2	4,682,209		4,781,421
Year 3	4,487,028		6,441,207
Year 4	6,166,402		3,513,075
Year 5	3,373,843		2,244,179
Prior	6,846,666		4,939,166
Revolving Loans	10,921,113		10,847,445
Revolving Loans Converted to Term Loans	104,022		88,358
Total	37,990,704		37,672,102
Converted to term loan	16,000	7,000
Commercial lending | Gross write-offs
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Gross write-offs year 1	0		20
Gross write-offs year 2	0		47,963
Gross write-offs year 3	0		17,137
Gross write-offs year 4	46		11,119
Gross write-offs year 5	437		1,568
Gross write-offs year Prior	14,175		3,025
Gross write-offs year Revolving Loans	0		27,099
Gross write-offs Revolving Loans Converted to Term Loans	0		0
Gross write-offs Total	14,658		107,931
Commercial lending | C&I
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	537,194		2,644,162
Year 2	2,543,887		1,589,544
Year 3	1,343,005		1,080,900
Year 4	996,145		730,036
Year 5	681,409		257,291
Prior	526,923		336,179
Revolving Loans	10,793,156		10,736,014
Revolving Loans Converted to Term Loans	39,025		23,032
Total	17,460,744		17,397,158
Gross write-offs Total	988	20,998
Commercial lending | C&I | Pass
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	536,257		2,605,928
Year 2	2,495,604		1,508,948
Year 3	1,284,574		999,586
Year 4	924,021		612,015
Year 5	599,028		243,528
Prior	478,909		295,884
Revolving Loans	10,637,412		10,574,404
Revolving Loans Converted to Term Loans	39,025		23,032
Total	16,994,830		16,863,325
Commercial lending | C&I | Criticized (accrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	653		34,412
Year 2	43,822		51,415
Year 3	31,427		61,041
Year 4	50,138		107,355
Year 5	72,115		10,538
Prior	36,503		31,160
Revolving Loans	155,677		151,747
Revolving Loans Converted to Term Loans	0		0
Total	390,335		447,668
Commercial lending | C&I | Criticized (nonaccrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	284		3,822
Year 2	4,461		29,181
Year 3	27,004		20,273
Year 4	21,986		10,666
Year 5	10,266		3,225
Prior	11,511		9,135
Revolving Loans	67		9,863
Revolving Loans Converted to Term Loans	0		0
Total	75,579		86,165
Commercial lending | C&I | Gross write-offs
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Gross write-offs year 1	0		20
Gross write-offs year 2	0		47,963
Gross write-offs year 3	0		14,848
Gross write-offs year 4	46		11,119
Gross write-offs year 5	418		1,568
Gross write-offs year Prior	253		3,012
Gross write-offs year Revolving Loans	0		27,099
Gross write-offs Revolving Loans Converted to Term Loans	0		0
Gross write-offs Total	717		105,629
Commercial lending | CRE
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	626,306		1,695,420
Year 2	1,646,768		2,341,320
Year 3	2,309,782		3,782,603
Year 4	3,673,141		1,956,835
Year 5	1,932,701		1,373,773
Prior	4,505,287		3,344,525
Revolving Loans	110,625		96,791
Revolving Loans Converted to Term Loans	63,751		64,073
Total	14,868,361		14,655,340
Gross write-offs Total	13,937	2,398
Commercial lending | CRE | Pass
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	626,306		1,660,877
Year 2	1,612,384		2,296,763
Year 3	2,209,065		3,692,498
Year 4	3,559,562		1,925,220
Year 5	1,876,657		1,296,439
Prior	4,241,478		3,176,450
Revolving Loans	110,625		96,791
Revolving Loans Converted to Term Loans	49,000		49,302
Total	14,285,077		14,194,340
Commercial lending | CRE | Criticized (accrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	0		34,543
Year 2	34,384		44,557
Year 3	100,717		90,105
Year 4	113,114		31,615
Year 5	55,208		75,578
Prior	259,557		167,401
Revolving Loans	0		0
Revolving Loans Converted to Term Loans	14,751		14,771
Total	577,731		458,570
Commercial lending | CRE | Criticized (nonaccrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	0		0
Year 2	0		0
Year 3	0		0
Year 4	465		0
Year 5	836		1,756
Prior	4,252		674
Revolving Loans	0		0
Revolving Loans Converted to Term Loans	0		0
Total	5,553		2,430
Commercial lending | CRE | Gross write-offs
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Gross write-offs year 1	0		0
Gross write-offs year 2	0		0
Gross write-offs year 3	0		0
Gross write-offs year 4	0		0
Gross write-offs year 5	19		0
Gross write-offs year Prior	13,918		3
Gross write-offs year Revolving Loans	0		0
Gross write-offs Revolving Loans Converted to Term Loans	0		0
Gross write-offs Total	13,937		3
Commercial lending | Multifamily residential
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	226,636		386,743
Year 2	390,608		521,754
Year 3	504,267		1,381,596
Year 4	1,318,527		784,272
Year 5	738,607		613,115
Prior	1,810,746		1,250,069
Revolving Loans	17,332		14,640
Revolving Loans Converted to Term Loans	1,246		1,253
Total	5,007,969		4,953,442
Gross write-offs Total	4	6
Commercial lending | Multifamily residential | Pass
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	226,636		386,743
Year 2	390,608		521,754
Year 3	504,267		1,337,599
Year 4	1,269,597		752,230
Year 5	704,413		613,115
Prior	1,803,284		1,242,586
Revolving Loans	17,332		14,640
Revolving Loans Converted to Term Loans	1,246		1,253
Total	4,917,383		4,869,920
Commercial lending | Multifamily residential | Criticized (accrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	0		0
Year 2	0		0
Year 3	0		43,997
Year 4	48,930		32,042
Year 5	34,194		0
Prior	2,907		2,911
Revolving Loans	0		0
Revolving Loans Converted to Term Loans	0		0
Total	86,031		78,950
Commercial lending | Multifamily residential | Criticized (nonaccrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	0		0
Year 2	0		0
Year 3	0		0
Year 4	0		0
Year 5	0		0
Prior	4,555		4,572
Revolving Loans	0		0
Revolving Loans Converted to Term Loans	0		0
Total	4,555		4,572
Commercial lending | Multifamily residential | Gross write-offs
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Gross write-offs year 1	0		0
Gross write-offs year 2	0		0
Gross write-offs year 3	0		0
Gross write-offs year 4	0		0
Gross write-offs year 5	0		0
Gross write-offs year Prior	4		10
Gross write-offs year Revolving Loans	0		0
Gross write-offs Revolving Loans Converted to Term Loans	0		0
Gross write-offs Total	4		10
Commercial lending | Construction and land
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	19,285		90,926
Year 2	100,946		328,803
Year 3	329,974		196,108
Year 4	178,589		41,932
Year 5	21,126		0
Prior	3,710		8,393
Revolving Loans	0		0
Revolving Loans Converted to Term Loans	0		0
Total	653,630		666,162
Gross write-offs Total	1,996	1,224
Commercial lending | Construction and land | Pass
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	19,285		90,926
Year 2	100,946		328,803
Year 3	329,974		184,792
Year 4	178,589		41,932
Year 5	21,126		0
Prior	3,710		8,393
Revolving Loans	0		0
Revolving Loans Converted to Term Loans	0		0
Total	653,630		654,846
Commercial lending | Construction and land | Criticized (nonaccrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1			0
Year 2			0
Year 3			11,316
Year 4			0
Year 5			0
Prior			0
Revolving Loans			0
Revolving Loans Converted to Term Loans			0
Total			11,316
Commercial lending | Construction and land | Gross write-offs
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Gross write-offs year 1			0
Gross write-offs year 2			0
Gross write-offs year 3			2,289
Gross write-offs year 4			0
Gross write-offs year 5			0
Gross write-offs year Prior			0
Gross write-offs year Revolving Loans			0
Gross write-offs Revolving Loans Converted to Term Loans			0
Gross write-offs Total			2,289
Commercial lending | Total CRE
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	872,227		2,173,089
Year 2	2,138,322		3,191,877
Year 3	3,144,023		5,360,307
Year 4	5,170,257		2,783,039
Year 5	2,692,434		1,986,888
Prior	6,319,743		4,602,987
Revolving Loans	127,957		111,431
Revolving Loans Converted to Term Loans	64,997		65,326
Total	20,529,960		20,274,944
Gross write-offs year 1	0
Gross write-offs year 2	0
Gross write-offs year 3	0
Gross write-offs year 4	0
Gross write-offs year 5	19
Gross write-offs year Prior	13,922
Gross write-offs year Revolving Loans	0
Gross write-offs Revolving Loans Converted to Term Loans	0
Gross write-offs Total	13,941
Commercial lending | Total CRE | Gross write-offs
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Gross write-offs year 1			0
Gross write-offs year 2			0
Gross write-offs year 3			2,289
Gross write-offs year 4			0
Gross write-offs year 5			0
Gross write-offs year Prior			13
Gross write-offs year Revolving Loans			0
Gross write-offs Revolving Loans Converted to Term Loans			0
Gross write-offs Total			2,302
Consumer lending
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	709,027		2,394,531
Year 2	2,252,693		2,782,386
Year 3	2,684,812		3,108,350
Year 4	3,044,622		2,090,575
Year 5	2,043,618		1,419,106
Prior	3,746,160		2,480,697
Revolving Loans	1,682,357		1,673,296
Revolving Loans Converted to Term Loans	98,741		105,594
Total	16,262,030		16,054,535
Consumer lending | Gross write-offs
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Gross write-offs year 1	0		9
Gross write-offs year 2	9		3,010
Gross write-offs year 3	0		0
Gross write-offs year 4	0		0
Gross write-offs year 5	0		0
Gross write-offs year Prior	0		0
Gross write-offs year Revolving Loans	0		890
Gross write-offs Revolving Loans Converted to Term Loans	0		5
Gross write-offs Total	9		3,914
Consumer lending | Single-family residential
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	704,247		2,367,565
Year 2	2,239,483		2,776,003
Year 3	2,680,034		3,077,347
Year 4	3,014,039		2,087,168
Year 5	2,039,305		1,410,983
Prior	3,706,454		2,456,380
Revolving Loans	0		0
Revolving Loans Converted to Term Loans	0		0
Total	14,383,562		14,175,446
Gross write-offs Total	9	0
Consumer lending | Single-family residential | Pass
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	704,247		2,360,674
Year 2	2,230,645		2,762,921
Year 3	2,665,707		3,074,668
Year 4	3,007,253		2,079,323
Year 5	2,030,062		1,407,031
Prior	3,687,561		2,437,446
Revolving Loans	0		0
Revolving Loans Converted to Term Loans	0		0
Total	14,325,475		14,122,063
Consumer lending | Single-family residential | Criticized (accrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	0		4,175
Year 2	2,222		3,409
Year 3	2,622		750
Year 4	3,478		5,810
Year 5	1,786		1,548
Prior	6,631		6,069
Revolving Loans	0		0
Revolving Loans Converted to Term Loans	0		0
Total	16,739		21,761
Consumer lending | Single-family residential | Criticized (nonaccrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	0		2,716
Year 2	6,616		9,673
Year 3	11,705		1,929
Year 4	3,308		2,035
Year 5	7,457		2,404
Prior	12,262		12,865
Revolving Loans	0		0
Revolving Loans Converted to Term Loans	0		0
Total	41,348		31,622
Consumer lending | Single-family residential | Gross write-offs
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Gross write-offs year 1	0		9
Gross write-offs year 2	9		0
Gross write-offs year 3	0		0
Gross write-offs year 4	0		0
Gross write-offs year 5	0		0
Gross write-offs year Prior	0		0
Gross write-offs year Revolving Loans	0		0
Gross write-offs Revolving Loans Converted to Term Loans	0		0
Gross write-offs Total	9		9
Consumer lending | Home equity lines of credit (“HELOCs”)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	517		12,050
Year 2	12,531		6,383
Year 3	4,778		8,011
Year 4	7,579		3,275
Year 5	4,182		8,123
Prior	32,909		17,517
Revolving Loans	1,666,600		1,650,675
Revolving Loans Converted to Term Loans	98,741		105,594
Total	1,827,837		1,811,628
Gross write-offs Total	0	0
Consumer lending | Home equity lines of credit (“HELOCs”) | Pass
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	517		7,453
Year 2	6,812		3,288
Year 3	3,443		4,071
Year 4	3,388		3,236
Year 5	2,472		7,570
Prior	11,011		8,152
Revolving Loans	1,660,563		1,648,337
Revolving Loans Converted to Term Loans	92,591		99,488
Total	1,780,797		1,781,595
Consumer lending | Home equity lines of credit (“HELOCs”) | Criticized (accrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	0		1,436
Year 2	742		0
Year 3	183		1,420
Year 4	1,002		0
Year 5	1,658		135
Prior	11,015		2,064
Revolving Loans	6,037		2,338
Revolving Loans Converted to Term Loans	1,153		594
Total	21,790		7,987
Consumer lending | Home equity lines of credit (“HELOCs”) | Criticized (nonaccrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	0		3,161
Year 2	4,977		3,095
Year 3	1,152		2,520
Year 4	3,189		39
Year 5	52		418
Prior	10,883		7,301
Revolving Loans	0		0
Revolving Loans Converted to Term Loans	4,997		5,512
Total	25,250		22,046
Consumer lending | Home equity lines of credit (“HELOCs”) | Gross write-offs
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Gross write-offs year 1			0
Gross write-offs year 2			10
Gross write-offs year 3			0
Gross write-offs year 4			0
Gross write-offs year 5			0
Gross write-offs year Prior			0
Gross write-offs year Revolving Loans			0
Gross write-offs Revolving Loans Converted to Term Loans			5
Gross write-offs Total			15
Consumer lending | Total residential mortgage
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	704,764		2,379,615
Year 2	2,252,014		2,782,386
Year 3	2,684,812		3,085,358
Year 4	3,021,618		2,090,443
Year 5	2,043,487		1,419,106
Prior	3,739,363		2,473,897
Revolving Loans	1,666,600		1,650,675
Revolving Loans Converted to Term Loans	98,741		105,594
Total	16,211,399		15,987,074
Consumer lending | Total residential mortgage | Gross write-offs
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Gross write-offs year 1	0		9
Gross write-offs year 2	9		10
Gross write-offs year 3	0		0
Gross write-offs year 4	0		0
Gross write-offs year 5	0		0
Gross write-offs year Prior	0		0
Gross write-offs year Revolving Loans	0		0
Gross write-offs Revolving Loans Converted to Term Loans	0		5
Gross write-offs Total	9		24
Consumer lending | Other consumer
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	4,263		14,916
Year 2	679		0
Year 3	0		22,992
Year 4	23,004		132
Year 5	131		0
Prior	6,797		6,800
Revolving Loans	15,757		22,621
Revolving Loans Converted to Term Loans	0		0
Total	50,631		67,461
Gross write-offs Total	49	$ 58
Consumer lending | Other consumer | Pass
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	4,257		14,916
Year 2	679		0
Year 3	0		22,992
Year 4	23,004		132
Year 5	131		0
Prior	6,797		6,800
Revolving Loans	15,660		22,555
Revolving Loans Converted to Term Loans	0		0
Total	50,528		67,395
Consumer lending | Other consumer | Criticized (accrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	6
Year 2	0
Year 3	0
Year 4	0
Year 5	0
Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total	6
Consumer lending | Other consumer | Criticized (nonaccrual)
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Year 1	0		0
Year 2	0		0
Year 3	0		0
Year 4	0		0
Year 5	0		0
Prior	0		0
Revolving Loans	97		66
Revolving Loans Converted to Term Loans	0		0
Total	$ 97		66
Consumer lending | Other consumer | Gross write-offs
Financing Receivable, Vintage Year/Credit Quality Indicator [Line Items]
Gross write-offs year 1			0
Gross write-offs year 2			3,000
Gross write-offs year 3			0
Gross write-offs year 4			0
Gross write-offs year 5			0
Gross write-offs year Prior			0
Gross write-offs year Revolving Loans			890
Gross write-offs Revolving Loans Converted to Term Loans			0
Gross write-offs Total			$ 3,890