| **Income Taxes (Summary of Tax Net Operating Loss Carryforwards) (Details) $ in Thousands** | Dec. 31, 2016 USD ($) |
|---------------------------------------------------------------------------------------------|-----------------------|
| Federal                                                                                     |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | $ 272,054             |
| State                                                                                       |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 266,006               |
| 2022 | Federal                                                                              |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 10,236                |
| 2022 | State                                                                                |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 11,371                |
| 2023 | Federal                                                                              |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 3,968                 |
| 2023 | State                                                                                |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 3,903                 |
| 2024 | Federal                                                                              |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 722                   |
| 2024 | State                                                                                |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 0                     |
| 2025 | Federal                                                                              |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 737                   |
| 2025 | State                                                                                |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 0                     |
| 2026 | Federal                                                                              |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 150                   |
| 2026 | State                                                                                |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 0                     |
| 2027 | Federal                                                                              |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 1,010                 |
| 2027 | State                                                                                |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 0                     |
| 2028 | Federal                                                                              |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 39,879                |
| 2028 | State                                                                                |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 39,715                |
| 2029 | Federal                                                                              |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 48,370                |
| 2029 | State                                                                                |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 47,558                |
| 2031 | Federal                                                                              |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 110,933               |
| 2031 | State                                                                                |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 109,376               |
| 2033 | Federal                                                                              |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 5,031                 |
| 2033 | State                                                                                |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 4,927                 |
| 2034 | Federal                                                                              |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 39,133                |
| 2034 | State                                                                                |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 37,866                |
| 2035 | Federal                                                                              |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | 11,885                |
| 2035 | State                                                                                |                  |
| **Operating Loss Carryforwards [Line Items]**                                               |                  |
| Net operating loss carryforwards                                                            | $ 11,290              |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32559-109319
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