Other Borrowings - FHLB and FRB Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
FHLB Advances
Outstanding advances	$ 100,000	$ 0
Loans	$ 31,931,916	$ 29,821,418
Asset Pledged as Collateral [Member]
FHLB Advances
Financing Receivable, Pledging Purpose [Extensible Enumeration]	Federal Funds Purchased	Federal Funds Purchased
Short term borrowings
FHLB Advances
Long-term Debt, Weighted Average Interest Rate, over Time	5.08%	5.22%
FRB Borrowings \| Asset Not Pledged as Collateral and Asset Pledged as Collateral without Right [Member]
FHLB Advances
Outstanding advances	$ 1,900,000
Net eligible loans	2,700,000
FHLB Advances
FHLB Advances
Outstanding advances	100,000
Average amount of FHLB advances outstanding	243,000	$ 11,000
Total borrowing capacity at FHLB	7,100,000
FHLB Advances \| Loans [Member]
FHLB Advances
Loans pledged via a blanket lien to the FHLB for advances and letters of credit	11,400,000
Debt Instrument Collateral Amount	6,500,000
FHLB Advances \| Investments Securities and Cash [Member]
FHLB Advances
Investment securities pledged	729,400
Debt Instrument Collateral Amount	617,600
FHLB Advances
FHLB Advances
Letter of credit borrowed	2,900
Unused net credit available with the FHLB	7,000,000
FRB Borrowings
FHLB Advances
Letter of credit borrowed	0
Maximum borrowing capacity	$ 1,900,000
FRB Borrowings \| Asset Not Pledged as Collateral and Asset Pledged as Collateral without Right [Member]
FHLB Advances
Financing Receivable, Pledging Purpose [Extensible Enumeration]	Federal Funds Purchased

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of assets pledged to secure a debt instrument.

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The calculated average balance outstanding for the year for all Federal Home Loan Bank advances as of the Balance Sheet date.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Indicates pledging purpose of financing receivable.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Weighted average interest rate of long-term debt outstanding calculated over time.

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged by counterparties under financing and lending arrangements, pursuant to which the entity has the right by agreement or custom to sell or re-pledge such securities.

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