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Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Unrecognized tax benefits activity |  |
Beginning Balance | $ 5,517 | $ 5,501
Increase related to current year tax position |  |
Increase (decrease) related to prior year tax position |  | 16
Ending Balance | 5,517 | $ 5,517
Unrecognized tax benefits that would impact effective tax rate | 5,500 |
Accrued interest or penalties related to uncertain tax positions | $ 0 |

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- Definition Amount of unrecognized tax benefits. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 10B -URI http://asc.fasb.org/extlink&oid=116821951&loc=SL37586934-109318 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 + Details
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