Short-Term Borrowings and Long-Term FHLB Advances - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Federal Home Loan Bank, Advances [Line Items]
Long-term FHLB advances	$ 55,400	$ 55,400
Federal Home Loan Bank stock	10,526	$ 14,530
Federal Home Loan Bank maximum borrowing capacity	1,560,000
Federal Home Loan Bank, advances, amount available	1,400,000
Overnight federal funds
Federal Home Loan Bank, Advances [Line Items]
Federal Home Loan Bank, advances, amount available	71,000
Federal Reserve Discount Window
Federal Home Loan Bank, Advances [Line Items]
Federal Home Loan Bank, advances, amount available	$ 145,500

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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