Summary of Significant Accounting Policies - Significant Estimates Used by Management in Determining Fair Values of Customer Relationships Acquired (Detail) |
9 Months Ended | 12 Months Ended |
|---|---|---|
Sep. 30, 2018 |
Dec. 31, 2017 |
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| Minimum | ||
| Indefinite-lived Intangible Assets [Line Items] | ||
| Discount rates | 20.00% | 17.00% |
| Customer attrition rates | 20.00% | 15.00% |
| Maximum | ||
| Indefinite-lived Intangible Assets [Line Items] | ||
| Discount rates | 27.00% | 25.00% |
| Customer attrition rates | 33.00% | 78.00% |
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- Definition Fair Value Inputs, Customer Attrition Rates No definition available.
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- Definition Fair Value Inputs, Rate Of Return No definition available.
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- Definition 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. No definition available.
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