Other Borrowed Funds - Narrative (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Advance from Federal Home Loan Bank	$ 2,589.0	$ 2,327.0
5.01% fixed rate borrowings in tenors up to one-month
Advance from Federal Home Loan Bank	$ 450.0
Fixed-to-floating rate (percent)	5.39%
5.11% average fixed rate borrowings in tenors of 2-month
Advance from Federal Home Loan Bank	$ 600.0
Fixed-to-floating rate (percent)	5.38%
5.12% average fixed rate borrowings in tenors of 3-months
Advance from Federal Home Loan Bank	$ 150.0
Fixed-to-floating rate (percent)	5.56%
Notes Payable to FHLB \| Subsidiaries \| Federal Home Loan Bank Advances
Federal Home Loan Bank, Advances, General Debt Obligations, Amount of Available, Unused Funds	$ 4,517.6
Federal Home Loan Bank, Advances, General Debt Obligations, Maximum Amount Available	7,106.6
5.30% average fixed rate borrowings in tenors up to two-weeks
Advance from Federal Home Loan Bank	$ 553.0
Fixed-to-floating rate (percent)	5.30%
5.54% average fixed rate borrowings in tenors of 4-months
Advance from Federal Home Loan Bank	$ 400.0
Fixed-to-floating rate (percent)	5.54%
5.56% average fixed rate borrowings in tenors of 5-months
Advance from Federal Home Loan Bank	$ 436.0
Fixed-to-floating rate (percent)	5.56%

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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