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Fair Value Measurement and Fair Value of Financial Instruments (Quantitative Information for Significant Unobservable Inputs) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Quantitative information |  |
Derivative assets | $ 66,146 | $ 83,780
Available-for-sale investment securities | 3,016,752 | 3,335,795
Other securities |  |
Quantitative information |  |
Available-for-sale investment securities | 31,342 | 40,329
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) |  |
Quantitative information |  |
Derivative assets | 679 | 0
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Warrants |  |
Quantitative information |  |
Warrants | 679 |
Derivative assets | $ 679 |
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Warrants | Black-Scholes option pricing model | Weighted Average |  |
Quantitative information |  |
Volatility | 44.00% |
Liquidity discount | 47.00% |
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Other securities |  |
Quantitative information |  |
Available-for-sale investment securities | $ 0 | 0
Fair Value, Measurements, Nonrecurring | Non-PCI impaired loans |  |
Quantitative information |  |
Impaired loans | 38,188 | 70,154
Fair Value, Measurements, Nonrecurring | OREO |  |
Quantitative information |  |
OREO | 9 | 345
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans |  |
Quantitative information |  |
Impaired loans | 38,188 | 70,154
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Discounted cash flows |  |
Quantitative information |  |
Impaired loans | $ 22,802 | $ 31,835
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Discounted cash flows | Minimum |  |
Quantitative information |  |
Discount | 4.00% | 4.00%
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Discounted cash flows | Maximum |  |
Quantitative information |  |
Discount | 10.00% | 8.00%
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Discounted cash flows | Weighted Average |  |
Quantitative information |  |
Discount | 6.00% | 5.00%
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Fair value of collateral, discount |  |
Quantitative information |  |
Impaired loans | $ 3,207 | $ 18,417
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Fair value of collateral, discount | Minimum |  |
Quantitative information |  |
Discount | 20.00% | 0.00%
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Fair value of collateral, discount | Maximum |  |
Quantitative information |  |
Discount | 32.00% | 75.00%
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Fair value of collateral, discount | Weighted Average |  |
Quantitative information |  |
Discount | 29.00% | 35.00%
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Fair value of collateral, contract value |  |
Quantitative information |  |
Impaired loans | $ 2,406 | $ 4,961
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Fair value of property |  |
Quantitative information |  |
Impaired loans | $ 9,773 | $ 14,941
Selling cost | 8.00% |
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Fair value of property | Minimum |  |
Quantitative information |  |
Selling cost |  | 4.00%
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Fair value of property | Maximum |  |
Quantitative information |  |
Selling cost |  | 8.00%
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-PCI impaired loans | Fair value of property | Weighted Average |  |
Quantitative information |  |
Selling cost | 8.00% | 6.00%
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | OREO |  |
Quantitative information |  |
OREO | $ 9 | $ 345
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | OREO | Fair value of property |  |
Quantitative information |  |
OREO | $ 9 | $ 345
Selling cost | 8.00% | 8.00%
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | OREO | Fair value of property | Weighted Average |  |
Quantitative information |  |
Selling cost | 8.00% | 8.00%

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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 + Details
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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 + Details
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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 + Details
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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 + Details
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