Commitments, Off-Balance Sheet Arrangements, Legal Proceedings and Regulatory Matters (Details Textuals) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Line Items]
Expense Related to Qualified Affordable Housing Projects	$ 9,000,000	$ 9,000,000	$ 18,000,000	$ 17,000,000
Remaining Investment in Qualified Affordable Housing Projects	203,000,000		203,000,000		$ 215,000,000
Variable Interest Entity Reporting Entity Involvement Unfunded Obligation Amount	30,000,000		30,000,000		27,000,000
Qualified Affordable Housing Investments, Impairment Loss			0		0
Loans Repurchased Under Make Whole Requests	2,000,000		$ 2,000,000		5,000,000
Loans Sold To Outside Investors Loss ReimbursementSettlement Paid					0
Make Whole Requests, Loan Origination Date, Majority			Jan. 01, 2021
Loans Sold To Outside Investors Original Amount	4,000,000,000.0		$ 4,000,000,000.0
Loans Sold To Outside Investors Remaining Outstanding Amount	3,400,000,000		3,400,000,000
Mortgage Repurchase Reserve	734,000		734,000		835,000
Residential Mortgage Loans Sold With Recourse Risk	14,000,000		14,000,000		15,000,000
Residential Mortgage Loans Sold With Credit Recourse Risk	58,000,000		58,000,000		16,000,000
Residential Mortgage Loans with Credit Risk Recourse	0		0		0
SBA Loan Fund, Remaining Unfunded Equity Contribution	3,000,000		3,000,000
UnconsolidatedProjectsLowIncomeHousing [Member]
Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Line Items]
Other Investments	205,000,000		205,000,000		219,000,000
PrincipalInvestmentCommitment [Member]
Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Line Items]
Other Investments	$ 41,000,000		$ 41,000,000		$ 40,000,000