Fair Value Measurements - Summary of Changes in the Fair Value of Level 3 Contingent Consideration (Parenthetical) (Detail) - Level 3 [Member] - Contingent Consideration [Member] $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Increase in fair value of contingent consideration	$ 68
FeedbackNow [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Increase in fair value of contingent consideration	$ 100	$ 780
FeedbackNow [Member] \| Discount Rate [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value of contingent consideration discount rate	0.173	0.238
FeedbackNow [Member] \| Revenue Volatility [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value of contingent consideration discount rate	0.266	0.219

Value of input used to measure contingent consideration liability from business combination.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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