Federal Home Loan Bank Borrowings FHLB Text (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal home loan bank advances collateral pledged	$ 2,600,000,000	$ 2,500,000,000
Federal Home Loan Bank borrowings	420,144,000	693,681,000
Federal home loan bank advances maximum amount available	1,400,000,000	1,200,000,000
FHLB borrowings callable before maturity	0	0
Stock in federal home loan bank	$ 35,200,000	$ 46,100,000
Minimum
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal home loan bank advances collateral valuation percentage	50.00%
Ownership percentage of outstanding advances	3.00%
Maximum
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal home loan bank advances collateral valuation percentage	80.00%
Ownership percentage of outstanding advances	4.00%

Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Valuation Percentage

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- Definition

Federal Home Loan Stock Ownership as a Percent of Outstanding Advances

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- Definition

FHLB Borrowings Callable Before Maturity

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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-Publisher FASB
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-SubTopic 470
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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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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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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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