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Income Taxes Income Taxes (Narrative) (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 USD ($) | Dec. 31, 2018 USD ($)
Income Tax Disclosure [Abstract] |  |
Tax Cuts and Jobs Act, change in tax rate, income tax expense (benefit) |  | $ (18,400)
Net operating loss carryforward | $ 10,700 | 10,700
Income Tax Contingency [Line Items] |  |
Additions to tax positions of prior years | 547 | 547
Income tax penalties and interest accrued | $ 55 | 55
Tax Year 2017 |  |
Income Tax Contingency [Line Items] |  |
Additions to tax positions of prior years |  | 168
Tax Year 2016 |  |
Income Tax Contingency [Line Items] |  |
Additions to tax positions of prior years |  | 149
Tax Year 2015 |  |
Income Tax Contingency [Line Items] |  |
Additions to tax positions of prior years |  | $ 230

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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319 + Details
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