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Income Taxes (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Income Taxes [Abstract] |  |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 21.00% | 35.00% |
Deferred Income Tax Expense (Benefit) | $ 2,757 | $ (27,177) | $ (5,455)
PortionOfTaxBenefitRecordedPositionsMoreLikelyThanNotToBeSustained | 50.00% |  |
Income Tax Uncertainties [Abstract] |  |  |
Unrecognized Tax Benefits that Would Impact Effective Tax Rate | $ 3,600 | 4,800 |
Unrecognized Tax Benefits, Period Increase (Decrease) | (1,300) | (2,900) |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued | 1,000 | 2,300 |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense | (1,400) | (900) | (1,500)
Decrease in Unrecognized Tax Benefits is Reasonably Possible | (700) |  |
Increase in Unrecognized Tax Benefits is Reasonably Possible | 300 |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Balance beginning of period | 5,839 | 8,751 |
Additions based on tax positions related to current year | 700 | 135 |
Reductions for tax positions of prior years | 0 | (331) |
Reductions due to lapse of applicable statute of limitations | (1,954) | (2,699) |
Settlements | 0 | (17) |
Balance end of period | 4,585 | 5,839 | $ 8,751
Valuation Allowance [Abstract] |  |  |
Valuation Allowance, Amount | $ 0 | $ 0 |

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- Definition Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d)(3) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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