Advances from Federal Home Loan Bank (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Federal Home Loan Bank, Advances [Line Items]
Total FHLB advances	$ 944	$ 101,056
Monthly Amortizing Advances [Member]
Federal Home Loan Bank, Advances [Line Items]
Total FHLB advances	944	1,056
Within 1 Year	106
2 Years	404
3 Years	20
4 Years	20
5 Years	20
After 5 Years	374
Short-term Advances [Member]
Federal Home Loan Bank, Advances [Line Items]
Total FHLB advances	0	$ 100,000
Federal Home Loan Bank Advances [Member]
Federal Home Loan Bank, Advances [Line Items]
Federal home loan bank stock used as collateral for advances	17,900
FHLB maximum borrowing capacity	522,800
Federal home loan bank letters of credit used for public fund pledging	226,100
Federal home loan bank advances available	$ 295,800
Federal Home Loan Bank Advances [Member] \| Minimum [Member]
Federal Home Loan Bank, Advances [Line Items]
Federal home loan bank advances, interest rate	0.00%
Federal Home Loan Bank Advances [Member] \| Maximum [Member]
Federal Home Loan Bank, Advances [Line Items]
Federal home loan bank advances, interest rate	6.03%
Federal Home Loan Bank Advances [Member] \| Weighted Average [Member]
Federal Home Loan Bank, Advances [Line Items]
Federal home loan bank advances, interest rate	1.33%
Federal Home Loan Bank Advances [Member] \| Monthly Amortizing Advances [Member] \| Weighted Average [Member]
Federal Home Loan Bank, Advances [Line Items]
Federal home loan bank advances, interest rate	1.33%	1.53%
Federal Home Loan Bank Advances [Member] \| Short-term Advances [Member]
Federal Home Loan Bank, Advances [Line Items]
Maturity period of debt instrument	14 days
Federal Home Loan Bank Advances [Member] \| Advance 0.34%, due 1/06/16 [Member]
Federal Home Loan Bank, Advances [Line Items]
Federal home loan bank advances, interest rate		0.34%
Maturity date		Jan. 06, 2016

Amount of letters of credit provided by FHLB used for public fund pledging.

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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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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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