Revenue from Contracts with Customers - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Revenue From Contract With Customer [Abstract]
Receivables related to revenue from contract with customer	$ 610,300,000		$ 610,300,000		$ 516,100,000
Impairments related to revenue receivables	0	$ 0	0	$ 0
Deferred revenue	15,400,000		15,400,000		12,800,000
Deferred revenue recognized	7,000,000.0	$ 7,200,000	8,100,000	$ 14,700,000
Capitalized costs	$ 2,200,000		$ 2,200,000		$ 0