Fair Value Measurements (Details 2) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Investments in securities that are classified as level 3
Available-for-sale Securities	$ 429,125	$ 363,644
Discounted cash flow methodology [Member] \| Significant Unobservable Inputs (Level 3) \| Weighted Average [Member]
Investments in securities that are classified as level 3
Cumulative Prepayment	2.50%	2.50%
Cumulative Default	12.50%	12.80%
Loss Given Default	94.30%	94.20%
Cure Given Default	60.90%	60.90%
Pooled trust preferred securities \| Significant Unobservable Inputs (Level 3)
Investments in securities that are classified as level 3
Available-for-sale Securities	$ 1,624	$ 1,584
Pooled trust preferred securities \| Discounted cash flow methodology [Member] \| Significant Unobservable Inputs (Level 3) \| Minimum [Member]
Investments in securities that are classified as level 3
Cumulative Prepayment	0.00%	0.00%
Cumulative Default	5.00%	5.00%
Loss Given Default	85.00%	85.00%
Cure Given Default	0.00%	0.00%
Pooled trust preferred securities \| Discounted cash flow methodology [Member] \| Significant Unobservable Inputs (Level 3) \| Maximum [Member]
Investments in securities that are classified as level 3
Cumulative Prepayment	61.00%	62.00%
Cumulative Default	100.00%	100.00%
Loss Given Default	100.00%	100.00%
Cure Given Default	75.00%	75.00%
Collateral dependent impaired loans \| Significant Unobservable Inputs (Level 3)
Investments in securities that are classified as level 3
Fair Value	$ 33,974	$ 33,974
Other real estate owned and other foreclosed assets \| Significant Unobservable Inputs (Level 3)
Investments in securities that are classified as level 3
Fair Value	$ 2,898	$ 4,173

Fair Value Inputs, Cumulative Default

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- Definition

Fair Value Inputs, Cure Given Default

+ References

No definition available.

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- Definition

Fair Value Inputs, Loss Given Default

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No definition available.

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- Definition

Fair value inputs recurring quantitative information for level 3 instruments.

+ References

No definition available.

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- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a recurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

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- Definition

Rate at which loans or a loan portfolio are expected to prepay principal balances, used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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