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Valuation and Qualifying Accounts - Schedule of Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Allowance For Doubtful Accounts [Member] |  |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at Beginning of Period | $ 691 | $ 460 | $ 680
Charged to (Recovery of) Costs and Expense | 363 | 293 | (222)
Deductions | (193) | 62 | (2)
Balance at End of Period | 1,247 | 691 | 460
Deferred Tax Valuation Allowance [Member] |  |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at Beginning of Period | 3,172 | 2,447 | 1,924
Charged to (Recovery of) Costs and Expense | 942 | 725 | 626
Charged to Other Accounts (net) | 10,046 |  | (103)
Balance at End of Period | 14,160 | $ 3,172 | $ 2,447
Allowance for Convertible Notes Receivable [Member] |  |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |  |
Charged to (Recovery of) Costs and Expense | 2,000 |  |
Balance at End of Period | $ 2,000 |  |

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- Definition Amount of valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690 + Details
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- Definition Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690 + Details
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- Definition Amount of increase in valuation and qualifying accounts and reserves from charge to accounts other than cost and expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690 + Details
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