Federal Home Loan Bank Borrowings (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, Advances, Maturities Summary, Due in Next Twelve Months	$ 529,720
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate of Amounts Due within One Year of Balance Sheet Date	1.55%
Federal Home Loan Bank, Advances, Maturities Summary, Due in Year Two	$ 59,018
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate, One to Two Years from Balance Sheet Date	1.45%
Federal Home Loan Bank, Advances, Maturities Summary, Due in Year Three	$ 54,365
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate, Two to Three Years from Balance Sheet Date	2.89%
Federal Home Loan Bank, Advances, Maturities Summary, Due in Year Four	$ 37,045
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate, Three to Four Years from Balance Sheet Date	2.01%
Federal Home Loan Bank, Advances, Maturities Summary, Due in Year Five	$ 3,985
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate, Four to Five Years from Balance Sheet Date	1.93%
Federal Home Loan Bank, Advances, Maturities Summary, Due after Year Five	$ 9,548
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate, after Five Years from Balance Sheet Date	2.57%
Federal Home Loan Bank, Advances	$ 693,681
Weighted Average [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Weighted Average Interest Rate	1.69%

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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States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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-Section 45
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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due after five years of the Balance Sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(3)(a))
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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from four to five years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due within one year of the Balance Sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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-Subparagraph (SX 210.9-03(13)(3)(a))
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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from one to two years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from three to four years of the Balance Sheet date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from two to three years of the Balance Sheet date.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-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 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-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 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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