Number of institutions issuing debt.

No definition available.

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- Definition

Number of securities representing interests in tranches of trusts.

+ References

No definition available.

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- Definition

Number of Securities, Return to Accrual Status

+ References

No definition available.

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- Definition

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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-Publisher FASB
-Name Accounting Standards Codification
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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.

+ References

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

This element represents the amount of loss recognized for other than temporary impairments (OTTI) of investments in debt and equity securities.

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-Publisher FASB
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- Definition

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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Securities - (Details Textual)	3 Months Ended
Securities - (Details Textual)	Mar. 31, 2017 USD ($) security institution	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 704,305,000		$ 686,405,000
Gross gains on sales of securities available for sale	0	$ 0
Securities available for sale	$ 696,885,000		674,248,000
Number of securities representing interests in tranches of trusts (tranches) \| security	3
Number of institutions issuing debt \| institution	250
Number of securities, return to accrual status \| security	2
Trust preferred securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 22,646,000		23,749,000
Securities available for sale	17,823,000		18,389,000
Impairments	0
Secure government, public and trust deposits
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities pledged as collateral	654,378,000		642,447,000
Short-term borrowings
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities pledged as collateral	21,466,000		$ 24,426,000
Residential mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale debt securities	2,946,000
Sale proceeds	$ 2,946,000
Other equity securities
Schedule of Available-for-sale Securities [Line Items]
Sale proceeds		4,000
Amortized cost		75,000
Gross gains on sales of securities available for sale		$ 71,000