Federal Home Loan Bank Advances - Summary of FHLB Advances (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Federal Home Loan Bank, Advances [Line Items]
FHLB advances (fixed rates 0.00% to 4.96% and variable rates 0.20% to 0.29%) maturing October 2022 to January 2041	$ 3,253,177	$ 1,902,655
Fair value hedge basis adjustments and unamortized prepayment fees	(13,820)	(16,636)
Federal Home Loan Bank advances	$ 3,239,357	$ 1,886,019
Minimum \| FHLB Advances
Federal Home Loan Bank, Advances [Line Items]
Fixed rate	0.00%
Variable rate	0.20%
Maximum \| FHLB Advances
Federal Home Loan Bank, Advances [Line Items]
Fixed rate	4.96%
Variable rate	0.29%

Advances From Federal Home Loan Banks, Fair Value Hedge Basis adjustments And Unamortized Prepayment Fees

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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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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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