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v3.19.3.a.u2

Selected Balance Sheet Data - Schedule of Other Assets (Parenthetical) (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Other Assets [Line Items] |  |  |
Allowance of doubtful accounts | $ 512 | $ 514 |
Provision of bad debt expense | 114 | 291 | $ 219
Write-off receivables | 116 | 271 | $ 38
Reduction of accrued bonuses and other employee related expenses in settlement of employee notes receivable | $ 60 | $ 192 |
Minimum [Member] |  |  |
Other Assets [Line Items] |  |  |
Notes receivable due period | 1 year |  |
Maximum [Member] |  |  |
Other Assets [Line Items] |  |  |
Notes receivable due period | 5 years |  |

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