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Fair Value Measurement and Fair Value of Financial Instruments (Reconciliation of Assets and Liabilities Measured on Recurring Basis) (Details) - Fair Value, Measurements, Recurring - Significant Unobservable Inputs (Level 3) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2015 | Dec. 31, 2016
Reconciliation of the beginning and ending balances for major asset categories measured at fair value on a recurring basis using significant unobservable inputs (Level 3) |  |  |
Beginning balance | $ 0 |  |
Purchases, issues, sales, settlements: |  |  |
Liabilities measured using significant unobservable inputs on a recurring basis |  |  | $ 0
Warrants |  |  |
Reconciliation of the beginning and ending balances for major liability categories measured at fair value on a recurring basis using significant unobservable inputs (Level 3) |  |  |
Beginning balance | 0 |  |
Total gains (losses) for the period: |  |  |
Included in earnings | 0 |  |
Included in other comprehensive income | 0 |  |
Purchases, issues, sales, settlements: |  |  |
Issuances | 679,000 |  |
Sales | 0 |  |
Settlements | 0 |  |
Transfers out of Level 3 | 0 |  |
Ending balance | 679,000 |  |
Embedded Derivative Liabilities |  |  |
Reconciliation of the beginning and ending balances for major liability categories measured at fair value on a recurring basis using significant unobservable inputs (Level 3) |  |  |
Beginning balance |  | $ (3,392,000) |
Total gains (losses) for the period: |  |  |
Included in earnings |  | (20,000) |
Included in other comprehensive income |  | 0 |
Purchases, issues, sales, settlements: |  |  |
Issuances |  | 0 |
Sales |  | 0 |
Settlements |  | 3,412,000 |
Transfers out of Level 3 |  | 0 |
Ending balance |  | 0 |
Other securities |  |  |
Reconciliation of the beginning and ending balances for major asset categories measured at fair value on a recurring basis using significant unobservable inputs (Level 3) |  |  |
Beginning balance | 0 |  |
Transfer from held-to-maturity investment security to available-for-sale investment security | 115,615,000 |  |
Total gains (losses) for the period: |  |  |
Included in earnings | 1,156,000 |  |
Included in other comprehensive income | 0 |  |
Purchases, issues, sales, settlements: |  |  |
Issuances | 0 |  |
Sales | 116,771,000 |  |
Settlements | 0 |  |
Transfers out of Level 3 | 0 |  |
Ending balance | $ 0 |  |
Corporate debt securities | Non-investment grade |  |  |
Reconciliation of the beginning and ending balances for major asset categories measured at fair value on a recurring basis using significant unobservable inputs (Level 3) |  |  |
Beginning balance |  | 6,528,000 |
Total gains (losses) for the period: |  |  |
Included in earnings |  | 960,000 |
Included in other comprehensive income |  | 922,000 |
Purchases, issues, sales, settlements: |  |  |
Issuances |  | 0 |
Sales |  | 7,219,000 |
Settlements |  | 98,000 |
Transfers out of Level 3 |  | (1,093,000) |
Ending balance |  | $ 0 |

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- Definition Amount of gain (loss) recognized in the income statement of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + 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 (c)(1) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19279-110258 + Details
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