Short-Term Borrowings and Long-Term FHLB Advances - Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Federal Home Loan Bank, Advances [Line Items]
Long-term FHLB advances	$ 40,000	$ 39,900
Federal Home Loan Bank stock	4,332	$ 12,666
Federal Home Loan Bank maximum borrowing capacity	1,770,000
Federal Home Loan Bank, advances, amount available	1,730,000
Overnight federal funds
Federal Home Loan Bank, Advances [Line Items]
Federal Home Loan Bank, advances, amount available	74,000
Federal Reserve Discount Window
Federal Home Loan Bank, Advances [Line Items]
Federal Home Loan Bank, advances, amount available	$ 118,900

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

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

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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