Basis of Presentation and Significant Accounting Policies - Accounts Receivable (Details) - USD ($) $ in Thousands |
6 Months Ended | 12 Months Ended | |
|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Dec. 31, 2018 |
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| Accounts Receivable, Allowance for Credit Loss [Roll Forward] | |||
| Balance at beginning of period | $ 5,198 | $ 21,737 | $ 21,737 |
| Additions (reductions) charged to bad debt expense | (14,589) | ||
| Deductions for uncollectible receivables written off | (155) | (1,950) | |
| Additions charged to bad debt expense | 266 | $ 53,790 | |
| Balance at end of period | $ 5,309 | $ 5,198 | |
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- Definition Amount of allowance for credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of increase in allowance for credit loss on accounts receivable, from recovery. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of direct write-downs of accounts receivable charged against the allowance. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of expense (reversal of expense) for expected credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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