Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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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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Fixed interest rate related to the interest rate 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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Debt - Additional Information (Detail) - USD ($)			3 Months Ended		6 Months Ended
Debt - Additional Information (Detail) - USD ($)	Jun. 11, 2019	Mar. 15, 2019	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 10, 2019	Feb. 28, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Capitalized interest costs			$ 500,000	$ 300,000	$ 1,100,000	$ 500,000
Line of Credit Facility, Remaining Borrowing Capacity			11,500,000		11,500,000
Payments of debt issuance costs					967,000	$ 16,703,000
Senior Secured Term Loan B
Debt Instrument [Line Items]
Borrowings			545,000,000		$ 545,000,000
Interest rate during period					6.15%
Senior debt			$ 529,188,000		$ 529,188,000				$ 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					5.65%
Senior debt			273,000,000		$ 273,000,000				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					6.02%
Unused capacity, commitment fee percentage					0.50%
Principal available	$ 100,000,000						$ 125,000,000
Senior debt			$ 76,382,000		$ 76,382,000				$ 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						$ 143,000,000
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%