Securities sold under Agreements to Repurchase and Other Borrowed Funds (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Mar. 31, 2016
Other borrowed funds disclosures
Federal Home Loan Bank advances maturity period	8 years
Borrowings outstanding	$ 226,338	$ 332,512
Average interest rate of outstanding balances		0.49%
Federal Home Loan Bank Advances [Member]
Other borrowed funds disclosures
Total borrowing capacity available	355,100	$ 609,100
Borrowings outstanding	$ 223,265	328,968
Average interest rate of outstanding balances	0.46%
Federal Reserve Bank Advances [Member]
Other borrowed funds disclosures
Borrowings outstanding	$ 0	0
Available borrowing capacity	243,900	244,300
Securities Sold under Agreements to Repurchase [Member]
Other borrowed funds disclosures
Borrowings outstanding	3,073	3,544
Federal Funds Purchased [Member]
Other borrowed funds disclosures
Federal Funds purchased outstanding	$ 0	$ 0

Represents the maturity period for Federal Home Loan Bank advances.

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- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(b))
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- Definition

Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

+ References

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- Definition

The calculated weighted average interest rate for Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

+ References

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- Definition

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

+ References

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))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 03
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-Subparagraph 2, 3
-Article 9

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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.

+ References

No definition available.

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