Fair Value Measurement and Fair Value of Financial Instruments (Details 6) - Fair Value, Measurements, Nonrecurring - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Non-PCI impaired loans
Quantitative information
Impaired loans	$ 47,937	$ 70,154
OREO
Quantitative information
OREO	1,789	345
Significant Unobservable Inputs (Level 3) \| Non-PCI impaired loans
Quantitative information
Impaired loans	47,937	70,154
Significant Unobservable Inputs (Level 3) \| Non-PCI impaired loans \| Discounted cash flows
Quantitative information
Impaired loans	$ 30,563	$ 31,835
Significant Unobservable Inputs (Level 3) \| Non-PCI impaired loans \| Discounted cash flows \| Minimum
Quantitative information
Discount rate	0.00%	0.00%
Significant Unobservable Inputs (Level 3) \| Non-PCI impaired loans \| Discounted cash flows \| Maximum
Quantitative information
Discount rate	82.00%	62.00%
Significant Unobservable Inputs (Level 3) \| Non-PCI impaired loans \| Discounted cash flows \| Weighted Average
Quantitative information
Discount rate	19.00%	7.00%
Significant Unobservable Inputs (Level 3) \| Non-PCI impaired loans \| Market comparables
Quantitative information
Impaired loans	$ 17,374	$ 38,319
Significant Unobservable Inputs (Level 3) \| Non-PCI impaired loans \| Market comparables \| Minimum
Quantitative information
Discount rate	0.00%	0.00%
Significant Unobservable Inputs (Level 3) \| Non-PCI impaired loans \| Market comparables \| Maximum
Quantitative information
Discount rate	100.00%	100.00%
Significant Unobservable Inputs (Level 3) \| Non-PCI impaired loans \| Market comparables \| Weighted Average
Quantitative information
Discount rate	40.00%	18.00%
Significant Unobservable Inputs (Level 3) \| OREO
Quantitative information
OREO	$ 1,789	$ 345
Significant Unobservable Inputs (Level 3) \| OREO \| Appraisal
Quantitative information
OREO	$ 1,789	$ 345
Selling cost	8.00%	8.00%
Significant Unobservable Inputs (Level 3) \| OREO \| Appraisal \| Weighted Average
Quantitative information
Selling cost	8.00%	8.00%

Represents selling cost used as an input to measure fair value.

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- Definition

Impaired Loans, Fair Value Disclosure

+ References

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ 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 (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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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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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ 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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