Leases - Schedule of Supplemental Cash Flow Information Related to Operating Leases (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Cash paid for amounts included in the measurement of operating lease assets / liabilities
Cash used in operating activities related to operating leases	$ 582	$ 775	$ 2,059	$ 2,383
Right-of-use assets obtained in exchange for lease obligations	$ 138	$ 11,022	$ 231	$ 21,418