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Fair Value Measurements - Summary of Changes in the Fair Value of Level 3 Contingent Consideration (Parenthetical) (Detail) - FeedbackNow [Member] | Mar. 31, 2020 USD ($) | Jul. 06, 2018 USD ($)
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Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Business acquisition undiscounted amounts payable, minimum | $ 0 |
Business acquisition undiscounted amounts payable, maximum | $ 2,500,000 | $ 4,200,000
Level 3 [Member] | Discount Rate [Member] | Contingent Consideration [Member] |  |
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Fair value of contingent consideration discount rate | 0.173 |
Level 3 [Member] | Revenue Volatility [Member] | Contingent Consideration [Member] |  |
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Fair value of contingent consideration discount rate | 0.266 |

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