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v3.19.3.a.u2

Schedule II Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Allowance for doubtful accounts and returns |  |  |
Changes in Valuation and Qualifying Accounts |  |  |
Balance at Beginning of Period |  |  | $ 77
Charged to Costs and Expenses | $ 818 |  |
Deductions |  | $ 0 | 77
Balance at End of Period | 818 |  |
Deferred tax valuation allowance |  |  |
Changes in Valuation and Qualifying Accounts |  |  |
Balance at Beginning of Period | 6,835 | 7,136 | 122,966
Charged to Costs and Expenses | 1,492 | (441) | (115,831)
Deductions |  | (140) | (1)
Balance at End of Period | $ 8,327 | $ 6,835 | $ 7,136

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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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