FHLB Advances - Schedule of Maturities of Federal Home Loan Bank Advances (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Federal Home Loan Bank, Advances, Maturity, Rolling Year, Par Value [Abstract]
2019	1.58%
2020	7.47%
2021	1.45%
2022	7.47%
2023	7.47%
Thereafter	7.47%
2019	$ 22,386
2020	39
2021	7,042
2022	46
2023	49
Thereafter	448
Total	$ 30,010	$ 34,693

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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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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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.

+ References

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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.

+ References

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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.

+ References

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
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-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the remainder of the 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.

+ References

No definition available.

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Weighted average interest rate on advances made and reported by Federal Home Loan Bank (FHLBank) maturing after the fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Weighted average interest rate on advances made and reported by Federal Home Loan Bank (FHLBank) maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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Weighted average interest rate on advances made and reported by Federal Home Loan Bank (FHLBank) maturing in the fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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Weighted average interest rate on advances made and reported by Federal Home Loan Bank (FHLBank) maturing in the fourth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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Weighted average interest rate on advances made and reported by Federal Home Loan Bank maturing in the third rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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Weighted average interest rate on advances made and reported by Federal Home Loan Bank (FHLBank) maturing in the second rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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