Loans and Leases - Loans Held for Investment by Credit Quality Indicator (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Total	$ 68,272	$ 84,619
Year to date gross charge-offs
Total	(938)	(223)	$ (7)
Loans held for investment | Multi-family
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	19	840
Originated year two	837	8,066
Originated year three	7,929	8,182
Originated year four	7,776	7,924
Originated year five	7,649	4,040
Prior year	9,850	8,167
Revolving Loans	33	46
Revolving Loans Converted to Term Loans	0	0
Total	34,093	37,265
Year to date gross charge-offs
Originated year one	0	0
Originated year two	0	(112)
Originated year three	(28)	0
Originated year four	(34)	0
Originated year five	(42)	0
Prior year	(204)	(7)
Revolving Loans	0	0
Revolving Loans Converted to Term Loans	0	0
Total	(308)	(119)	(1)
Loans held for investment | Multi-family | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	17	840
Originated year two	700	7,945
Originated year three	6,599	7,967
Originated year four	6,070	7,310
Originated year five	5,203	3,525
Prior year	3,997	6,537
Revolving Loans	27	46
Revolving Loans Converted to Term Loans	0	0
Total	22,613	34,170
Loans held for investment | Multi-family | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	0	0
Originated year two	14	95
Originated year three	688	33
Originated year four	694	377
Originated year five	646	36
Prior year	795	227
Revolving Loans	1	0
Revolving Loans Converted to Term Loans	0	0
Total	2,838	768
Loans held for investment | Multi-family | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	2	0
Originated year two	123	21
Originated year three	529	176
Originated year four	868	237
Originated year five	1,526	451
Prior year	3,834	1,304
Revolving Loans	5	0
Revolving Loans Converted to Term Loans	0	0
Total	6,887	2,189
Loans held for investment | Multi-family | Non-accrual
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	0	0
Originated year two	0	5
Originated year three	113	6
Originated year four	144	0
Originated year five	274	28
Prior year	1,224	99
Revolving Loans	0	0
Revolving Loans Converted to Term Loans	0	0
Total	1,755	138
Loans held for investment | Commercial real estate
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	246	924
Originated year two	846	2,281
Originated year three	1,860	1,242
Originated year four	1,115	1,011
Originated year five	844	1,370
Prior year	3,314	3,458
Revolving Loans	89	183
Revolving Loans Converted to Term Loans	371	1
Total	8,685	10,470
Year to date gross charge-offs
Originated year one	0	0
Originated year two	(8)	0
Originated year three	(81)	0
Originated year four	(1)	0
Originated year five	(27)	0
Prior year	(345)	(56)
Revolving Loans	0	0
Revolving Loans Converted to Term Loans	0	0
Total	(462)	(56)	(4)
Loans held for investment | Commercial real estate | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	245	880
Originated year two	751	2,110
Originated year three	1,614	1,182
Originated year four	987	939
Originated year five	575	1,011
Prior year	2,011	2,439
Revolving Loans	89	172
Revolving Loans Converted to Term Loans	365	1
Total	6,637	8,734
Loans held for investment | Commercial real estate | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	0	0
Originated year two	47	122
Originated year three	49	12
Originated year four	30	0
Originated year five	106	116
Prior year	138	106
Revolving Loans	0	11
Revolving Loans Converted to Term Loans	0	0
Total	370	367
Loans held for investment | Commercial real estate | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	1	44
Originated year two	12	49
Originated year three	168	47
Originated year four	63	72
Originated year five	162	239
Prior year	720	790
Revolving Loans	0	0
Revolving Loans Converted to Term Loans	6	0
Total	1,132	1,241
Loans held for investment | Commercial real estate | Non-accrual
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	0	0
Originated year two	36	0
Originated year three	29	1
Originated year four	35	0
Originated year five	1	4
Prior year	445	123
Revolving Loans	0	0
Revolving Loans Converted to Term Loans	0	0
Total	546	128
Loans held for investment | One-to-four family first mortgage
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	251	527
Originated year two	527	2,643
Originated year three	2,455	939
Originated year four	871	238
Originated year five	201	326
Prior year	809	1,300
Revolving Loans	85	78
Revolving Loans Converted to Term Loans	2	10
Total	5,201	6,061
Year to date gross charge-offs
Originated year one	0	0
Originated year two	0	0
Originated year three	(1)	(1)
Originated year four	0	0
Originated year five	0	(1)
Prior year	(7)	(2)
Revolving Loans	0	0
Revolving Loans Converted to Term Loans	0	0
Total	(8)	(4)	0
Loans held for investment | One-to-four family first mortgage | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	250	526
Originated year two	521	2,627
Originated year three	2,431	920
Originated year four	859	210
Originated year five	178	239
Prior year	609	721
Revolving Loans	80	78
Revolving Loans Converted to Term Loans	2	7
Total	4,930	5,328
Loans held for investment | One-to-four family first mortgage | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one		0
Originated year two		0
Originated year three		0
Originated year four		0
Originated year five		0
Prior year		0
Revolving Loans		0
Revolving Loans Converted to Term Loans		0
Total		0
Loans held for investment | One-to-four family first mortgage | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	1	0
Originated year two	2	5
Originated year three	8	2
Originated year four	2	20
Originated year five	16	69
Prior year	172	542
Revolving Loans	0	0
Revolving Loans Converted to Term Loans	0	0
Total	201	638
Loans held for investment | One-to-four family first mortgage | Non-accrual
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	0	1
Originated year two	4	11
Originated year three	16	17
Originated year four	10	8
Originated year five	7	18
Prior year	28	37
Revolving Loans	5	0
Revolving Loans Converted to Term Loans	0	3
Total	70	95
Loans held for investment | Acquisition, development, and construction
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	298	406
Originated year two	592	329
Originated year three	236	330
Originated year four	206	34
Originated year five	4	4
Prior year	62	21
Revolving Loans	1,751	1,688
Revolving Loans Converted to Term Loans	2	100
Total	3,151	2,912
Year to date gross charge-offs
Originated year one	0	0
Originated year two	0	0
Originated year three	0	0
Originated year four	0	0
Originated year five	0	0
Prior year	(4)	0
Revolving Loans	0	0
Revolving Loans Converted to Term Loans	0	0
Total	(4)	0	0
Loans held for investment | Acquisition, development, and construction | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	297	406
Originated year two	547	322
Originated year three	139	298
Originated year four	119	4
Originated year five	1	4
Prior year	57	6
Revolving Loans	1,508	1,685
Revolving Loans Converted to Term Loans	2	100
Total	2,670	2,825
Loans held for investment | Acquisition, development, and construction | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	0	0
Originated year two	25	0
Originated year three	81	24
Originated year four	39	30
Originated year five	0	0
Prior year	0	0
Revolving Loans	120	3
Revolving Loans Converted to Term Loans	0	0
Total	265	57
Loans held for investment | Acquisition, development, and construction | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	1	0
Originated year two	19	6
Originated year three	11	7
Originated year four	47	0
Originated year five	0	0
Prior year	3	15
Revolving Loans	117	0
Revolving Loans Converted to Term Loans	0	0
Total	198	28
Loans held for investment | Acquisition, development, and construction | Non-accrual
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	0	0
Originated year two	1	1
Originated year three	5	1
Originated year four	1	0
Originated year five	3	0
Prior year	2	0
Revolving Loans	6	0
Revolving Loans Converted to Term Loans	0	0
Total	18	2
Loans held for investment | Commercial and industrial
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	1,300	9,428
Originated year two	2,693	3,767
Originated year three	2,264	1,695
Originated year four	736	1,019
Originated year five	467	764
Prior year	798	846
Revolving Loans	5,940	7,679
Revolving Loans Converted to Term Loans	1,178	56
Total	15,376	25,254
Year to date gross charge-offs
Originated year one		(2)
Originated year two		(7)
Originated year three		(1)
Originated year four		(7)
Originated year five		0
Prior year		(14)
Revolving Loans		0
Revolving Loans Converted to Term Loans		0
Total		(31)
Loans held for investment | Commercial and industrial | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	1,267	9,418
Originated year two	2,609	3,547
Originated year three	2,014	1,633
Originated year four	651	984
Originated year five	450	719
Prior year	759	791
Revolving Loans	5,554	7,535
Revolving Loans Converted to Term Loans	1,164	56
Total	14,468	24,683
Loans held for investment | Commercial and industrial | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	17	1
Originated year two	29	182
Originated year three	18	17
Originated year four	4	8
Originated year five	2	6
Prior year	11	20
Revolving Loans	119	101
Revolving Loans Converted to Term Loans	6	0
Total	206	335
Loans held for investment | Commercial and industrial | Substandard
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	13	7
Originated year two	50	24
Originated year three	72	43
Originated year four	72	16
Originated year five	7	38
Prior year	13	33
Revolving Loans	265	32
Revolving Loans Converted to Term Loans	8	0
Total	500	193
Loans held for investment | Commercial and industrial | Non-accrual
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	3	2
Originated year two	5	14
Originated year three	160	2
Originated year four	9	11
Originated year five	8	1
Prior year	15	2
Revolving Loans	2	11
Revolving Loans Converted to Term Loans	0	0
Total	202	43
Other loans held for investment
Year to date gross charge-offs
Total	(156)	(44)	$ (2)
Other loans held for investment | Commercial and industrial
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Total	13,260	22,065
Year to date gross charge-offs
Originated year one	(3)
Originated year two	(20)
Originated year three	(40)
Originated year four	(20)
Originated year five	(19)
Prior year	(34)
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total	(136)
Other loans held for investment | Other
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	100	171
Originated year two	29	348
Originated year three	12	245
Originated year four	4	134
Originated year five	2	134
Prior year	37	119
Revolving Loans	1,461	1,227
Revolving Loans Converted to Term Loans	121	279
Total	1,766	2,657
Year to date gross charge-offs
Originated year one	(2)	0
Originated year two	(4)	(3)
Originated year three	(4)	(4)
Originated year four	(1)	(1)
Originated year five	(1)	(2)
Prior year	(8)	(4)
Revolving Loans	0	0
Revolving Loans Converted to Term Loans	0	0
Total	(20)	(14)
Other loans held for investment | Other | Pass
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	100	171
Originated year two	29	346
Originated year three	12	244
Originated year four	4	133
Originated year five	2	133
Prior year	32	117
Revolving Loans	1,441	1,223
Revolving Loans Converted to Term Loans	121	268
Total	1,741	2,635
Other loans held for investment | Other | Special Mention
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	0
Originated year two	0
Originated year three	0
Originated year four	0
Originated year five	0
Prior year	0
Revolving Loans	1
Revolving Loans Converted to Term Loans	0
Total	1
Other loans held for investment | Other | Non-accrual
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, by Origination Year [Abstract]
Originated year one	0	0
Originated year two	0	2
Originated year three	0	1
Originated year four	0	1
Originated year five	0	1
Prior year	5	2
Revolving Loans	19	4
Revolving Loans Converted to Term Loans	0	11
Total	$ 24	$ 22