Loans and Leases - TDRs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Modified [Line Items]
Accruing		$ 16
Non- Accrual		28
Total	$ 262	44
Mortgage Loans | Multi-family
Financing Receivable, Modified [Line Items]
Accruing		0
Non- Accrual		6
Total	122	6
Mortgage Loans | Commercial real estate
Financing Receivable, Modified [Line Items]
Accruing		16
Non- Accrual		19
Total	103	35
Mortgage Loans | One-to-four family first mortgage
Financing Receivable, Modified [Line Items]
Total	14
Other Loans: | Commercial and industrial
Financing Receivable, Modified [Line Items]
Accruing		0
Non- Accrual		3
Total	21	$ 3
Other Loans: | Other
Financing Receivable, Modified [Line Items]
Total	$ 2