Securities sold under agreements to repurchase and Other Borrowed Funds (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016	Oct. 05, 2017
Other borrowed funds disclosures
Federal Home Loan Bank advances maturity period	1 year	2 years
Borrowings outstanding	$ 220,867	$ 153,493
Average interest rate of outstanding balances	1.15%
Available borrowing capacity			$ 373,300
Federal Home Loan Bank Advances [Member]
Other borrowed funds disclosures
Total borrowing capacity available	$ 1,100,000	608,800
Borrowings outstanding	215,000	$ 150,000
Average interest rate of outstanding balances		0.59%
Federal Reserve Bank Advances [Member]
Other borrowed funds disclosures
Borrowings outstanding	0	$ 0
Available borrowing capacity	53,800	330,000
Securities Sold under Agreements to Repurchase [Member]
Other borrowed funds disclosures
Borrowings outstanding	5,867	3,493
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.

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

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

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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
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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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