Revenue - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2019
Revenue From Contract With Customer [Abstract]
Deferred revenue expect to recognize description	We expect to recognize $2.8 million of deferred revenue related to material right performance obligations in the remainder of 2019, $10.5 million of such deferred revenue in 2020, and $60.1 million of such deferred revenue thereafter.