Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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The average effective interest rate during the reporting period.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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No definition available.

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- Definition

Fixed interest rate related to the interest rate derivative.

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No definition available.

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Nominal or face amount used to calculate payment on derivative.

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Amount of interest capitalized during the period.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Debt - Additional Information (Detail) - USD ($)			3 Months Ended		9 Months Ended
Debt - Additional Information (Detail) - USD ($)	Jun. 11, 2019	Mar. 15, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Feb. 28, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Capitalized interest costs			$ 400,000	$ 300,000	$ 1,500,000	$ 800,000
Remaining borrowing capacity			16,700,000		16,700,000
Payments of debt issuance costs					1,016,000	$ 20,703,000
Senior Secured Term Loan B
Debt Instrument [Line Items]
Borrowings			545,000,000		$ 545,000,000
Interest rate during period					5.80%
Senior debt			$ 527,750,000		$ 527,750,000			$ 532,063,000
Senior Secured Term Loan B \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Applicable margin					3.75%
Senior Secured Term Loan B \| London Interbank Offered Rate (LIBOR) \| Minimum
Debt Instrument [Line Items]
Interest rate			0.75%		0.75%
Incremental Term Loan
Debt Instrument [Line Items]
Borrowings			$ 300,000,000		$ 300,000,000
Interest rate during period					5.30%
Senior debt			270,000,000		$ 270,000,000			279,000,000
Incremental Term Loan \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Applicable margin					3.25%
Senior Secured Revolving Facility
Debt Instrument [Line Items]
Interest rate during period					5.73%
Unused capacity, commitment fee percentage					0.50%
Principal available			100,000,000		$ 100,000,000
Senior debt			$ 71,323,000		$ 71,323,000			$ 38,720,000
Payments of debt issuance costs	$ 200,000	$ 800,000
Write off of deferred debt issuance cost		$ 2,700,000
Maximum borrowing capacity	$ 110,000,000
Senior Secured Revolving Facility \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Applicable margin					3.50%
Senior Secured Revolving Facility \| Prime Rate
Debt Instrument [Line Items]
Applicable margin					2.50%
Interest Rate Swap
Debt Instrument [Line Items]
Derivative, notional amount							$ 700,000,000
Derivative, fixed interest rate							2.4575%