Fair Value Measurements - Schedule of Reconciliation of Contingent Consideration Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands |
9 Months Ended | 12 Months Ended |
|---|---|---|
Sep. 30, 2018 |
Dec. 31, 2017 |
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| Fair Value Assets Measured On Recurring and Nonrecurring Basis [Line Items] | ||
| Ending Balance | $ 1,806 | |
| Contingent Consideration [Member] | ||
| Fair Value Assets Measured On Recurring and Nonrecurring Basis [Line Items] | ||
| Beginning balance | 0 | $ 0 |
| Contingent consideration in connection with acquisitions | 1,720 | 0 |
| Change in fair value of contingent consideration | 86 | 0 |
| Payments of contingent consideration | 0 | 0 |
| Ending Balance | $ 1,806 | $ 0 |
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- Definition Fair Value Assets Measured On Recurring and Nonrecurring Basis [Line Items] No definition available.
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- Definition Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of increase (decrease) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy. No definition available.
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- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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