Long-Term Debt - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Principal amount	$ 800,000,000		$ 800,000,000			$ 765,000,000
Weighted average interest rate	2.70%	4.20%	3.00%	4.10%
Minimum
Debt Instrument [Line Items]
Interest rate margin			2.50%
Revolving credit facility interest rate percent above LIBOR alternate interest rate			1.50%
Commitment fee percentage	0.50%		0.50%
Maximum
Debt Instrument [Line Items]
Interest rate margin			3.50%
Revolving credit facility interest rate percent above LIBOR alternate interest rate			2.50%
Amended Credit Facility
Debt Instrument [Line Items]
Debt instrument, maturity date			Sep. 14, 2023
Line of credit facility, maximum borrowing capacity	$ 300,000,000.0		$ 300,000,000.0		$ 500,000,000.0
Principal amount	175,000,000		175,000,000			$ 140,000,000
Letters of credit issued amount	21,700,000		21,700,000
Line of credit facility, remaining borrowing capacity	53,300,000		53,300,000
Permitted Debt Resulting in Accelerated Maturity Date	100,000,000.0		100,000,000.0
Line of Credit Facility, Required Availability under the Credit Facility	50,000,000.0		50,000,000.0
Line of Credit Facility, Maximum Weekly Cash Balance	$ 35,000,000.0		$ 35,000,000.0