Debt - Summary of Long-Term Debt (Parenthetical) (Detail)	Jun. 30, 2019	Dec. 31, 2018
2023 Facility
Debt Instrument [Line Items]
Weighted average interest rate	4.40%	3.90%
2024 Term Loan
Debt Instrument [Line Items]
Weighted average interest rate	5.70%	5.20%

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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Period Type:	duration