Other Borrowed Funds - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Advance from Federal Home Loan Bank	$ 2,710.0	$ 2,327.0
5.01% fixed rate borrowings in tenors up to one-month
Advance from Federal Home Loan Bank	$ 850.0
Fixed-to-floating rate (percent)	5.01%
5.11% average fixed rate borrowings in tenors of 2-month
Advance from Federal Home Loan Bank	$ 800.0
Fixed-to-floating rate (percent)	5.11%
5.12% average fixed rate borrowings in tenors of 3-months
Advance from Federal Home Loan Bank	$ 1,060.0
Fixed-to-floating rate (percent)	5.12%
Notes Payable to FHLB \| Subsidiaries \| Federal Home Loan Bank Advances
Federal Home Loan Bank, Advances, General Debt Obligations, Amount of Available, Unused Funds	$ 3,678.7
Federal Home Loan Bank, Advances, General Debt Obligations, Maximum Amount Available	$ 6,388.7

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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