Composition of Certain Financial Statement Captions - Schedule of allowance for doubtful accounts (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Allowance for Doubtful Accounts | |||
| Balance at Beginning of Period | $ 3,633 | $ 2,165 | $ 1,218 |
| Additions | 5,274 | 3,508 | 2,085 |
| Write-offs, Net of Recoveries | (3,555) | (2,040) | (1,138) |
| Balance at End of Period | $ 5,352 | $ 3,633 | $ 2,165 |
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- Definition For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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/presentationRef
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- Definition Amount of increase (decrease) in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from adjustments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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