Borrowings (Details Textual) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Borrowings
Repurchase Agreements	$ 473,650,000	$ 423,414,000
Securities Pledged for Repurchase Agreements	472,239,000	446,838,000
FHLB advances	251,749,000	$ 394,131,000
Lines of credit	255,000,000
FHLB Put Options
Borrowings
FHLB advances	$ 155,000,000
Minimum rate to exercise put option	8.00%
FHLB Advances, Due Date, Earliest	2018
FHLB Advances, Due Date, Last	2021
FHLB Put Options \| Minimum Range
Borrowings
FHLB Advances, Interest Rate	2.73%
FHLB Put Options \| Maximum Range
Borrowings
FHLB Advances, Interest Rate	3.43%

Minimum rate to exercise put option.

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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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The earliest year of maturity for the advances from the Federal Home Loan Bank 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 45
-Paragraph 1
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The last year of maturity for the advances from the Federal Home Loan Bank as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02.19(b),22(b))
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- Definition

The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for repurchase agreements, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

+ References

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