Fair Value Measurement and Fair Value of Financial Instruments (Quantitative Information for Significant Unobservable Inputs) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Quantitative information
Equity warrant	$ 81,456	$ 66,146
Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Quantitative information
Equity warrant	648	679
Non-PCI Loans \| Fair Value, Measurements, Nonrecurring
Quantitative information
Non-PCI impaired loans	25,135	38,188
Non-PCI Loans \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Nonrecurring
Quantitative information
Non-PCI impaired loans	25,135	38,188
Non-PCI Loans \| Significant Unobservable Inputs (Level 3) \| Discounted cash flows \| Fair Value, Measurements, Nonrecurring
Quantitative information
Non-PCI impaired loans	$ 21,048	$ 22,802
Non-PCI Loans \| Significant Unobservable Inputs (Level 3) \| Discounted cash flows \| Fair Value, Measurements, Nonrecurring \| Weighted Average
Quantitative information
Discount	6.00%	6.00%
Non-PCI Loans \| Significant Unobservable Inputs (Level 3) \| Discounted cash flows \| Fair Value, Measurements, Nonrecurring \| Minimum
Quantitative information
Discount	4.00%	4.00%
Non-PCI Loans \| Significant Unobservable Inputs (Level 3) \| Discounted cash flows \| Fair Value, Measurements, Nonrecurring \| Maximum
Quantitative information
Discount	7.00%	10.00%
Non-PCI Loans \| Significant Unobservable Inputs (Level 3) \| Fair value of property \| Fair Value, Measurements, Nonrecurring
Quantitative information
Non-PCI impaired loans	$ 3,167	$ 9,773
Selling cost	8.00%	8.00%
Non-PCI Loans \| Significant Unobservable Inputs (Level 3) \| Fair value of property \| Fair Value, Measurements, Nonrecurring \| Weighted Average
Quantitative information
Selling cost	8.00%	8.00%
Non-PCI Loans \| Significant Unobservable Inputs (Level 3) \| Fair value of collateral, discount \| Fair Value, Measurements, Nonrecurring
Quantitative information
Non-PCI impaired loans	$ 318	$ 3,207
Discount	15.00%
Non-PCI Loans \| Significant Unobservable Inputs (Level 3) \| Fair value of collateral, discount \| Fair Value, Measurements, Nonrecurring \| Weighted Average
Quantitative information
Discount	15.00%	29.00%
Non-PCI Loans \| Significant Unobservable Inputs (Level 3) \| Fair value of collateral, discount \| Fair Value, Measurements, Nonrecurring \| Minimum
Quantitative information
Discount		20.00%
Non-PCI Loans \| Significant Unobservable Inputs (Level 3) \| Fair value of collateral, discount \| Fair Value, Measurements, Nonrecurring \| Maximum
Quantitative information
Discount		32.00%
Non-PCI Loans \| Significant Unobservable Inputs (Level 3) \| Fair value of collateral, contract value \| Fair Value, Measurements, Nonrecurring
Quantitative information
Non-PCI impaired loans	$ 602	$ 2,406
OREO non-recurring fair value losses \| Fair Value, Measurements, Nonrecurring
Quantitative information
OREO		9
OREO non-recurring fair value losses \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Nonrecurring
Quantitative information
OREO		9
OREO non-recurring fair value losses \| Significant Unobservable Inputs (Level 3) \| Fair value of property \| Fair Value, Measurements, Nonrecurring
Quantitative information
OREO		$ 9
Selling cost		8.00%
OREO non-recurring fair value losses \| Significant Unobservable Inputs (Level 3) \| Fair value of property \| Fair Value, Measurements, Nonrecurring \| Weighted Average
Quantitative information
Selling cost		8.00%
Equity warrants \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Quantitative information
Equity warrant	$ 648	$ 679
Equity warrants \| Significant Unobservable Inputs (Level 3) \| Black-Scholes option pricing model \| Fair Value, Measurements, Recurring \| Weighted Average
Quantitative information
Volatility	47.00%
Liquidity discount	47.00%

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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

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ 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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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

Adjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly.

+ 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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- 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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