Loans and Leases - Quality of Loans Held for Investment (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	$ 82,327	$ 84,619
Non- Accrual Loans	798	428
Loans 90 Days or More Delinquent and Still Accruing Interest	0	0
Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	212	250
Total Past Due Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	1,010	678
Current Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	81,317	83,941
Mortgage Loans:
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	56,196	56,708
Mortgage Loans: \| Multi-family
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	36,859	37,265
Non- Accrual Loans	339	138
Mortgage Loans: \| Multi-family \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	103	121
Mortgage Loans: \| Multi-family \| Total Past Due Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	442	259
Mortgage Loans: \| Multi-family \| Current Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	36,417	37,006
Mortgage Loans: \| Commercial real estate
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	10,323	10,470
Non- Accrual Loans	264	128
Mortgage Loans: \| Commercial real estate \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	9	28
Mortgage Loans: \| Commercial real estate \| Total Past Due Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	273	156
Mortgage Loans: \| Commercial real estate \| Current Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	10,050	10,314
Mortgage Loans: \| One-to-four family first mortgage
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	5,807	6,061
Non- Accrual Loans	98	95
Mortgage Loans: \| One-to-four family first mortgage \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	26	40
Mortgage Loans: \| One-to-four family first mortgage \| Total Past Due Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	124	135
Mortgage Loans: \| One-to-four family first mortgage \| Current Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	5,683	5,926
Mortgage Loans: \| Acquisition, development, and construction
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	3,207	2,912
Non- Accrual Loans	3	2
Mortgage Loans: \| Acquisition, development, and construction \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	6	2
Mortgage Loans: \| Acquisition, development, and construction \| Total Past Due Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	9	4
Mortgage Loans: \| Acquisition, development, and construction \| Current Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	3,198	2,908
Other Loans:
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	26,131	27,911
Other Loans: \| Commercial and industrial loans and lease financing
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	24,418	25,254
Non- Accrual Loans	73	43
Other Loans: \| Commercial and industrial loans and lease financing \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	60	37
Other Loans: \| Commercial and industrial loans and lease financing \| Total Past Due Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	133	80
Other Loans: \| Commercial and industrial loans and lease financing \| Current Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	24,285	25,174
Other Loans: \| Other
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	1,713	2,657
Non- Accrual Loans	21	22
Other Loans: \| Other \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	8	22
Other Loans: \| Other \| Total Past Due Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	29	44
Other Loans: \| Other \| Current Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	$ 1,684	$ 2,613

Amortized cost excluding accrued interest, of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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