Leases - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended		6 Months Ended
	Jul. 31, 2015	Feb. 28, 2015	Jun. 30, 2019
Lessee Operating Lease [Line Items]
Remaining rent payments			$ 4,153
Beaverton, Oregon [Member]
Lessee Operating Lease [Line Items]
Existence of option to extend			true
Option to extend operating lease			extend the lease term through March 2024
Option to extend operating lease, month and year	2024-03
Remaining rent payments			$ 4,054
San Mateo, California [Member]
Lessee Operating Lease [Line Items]
Remaining rent payments			$ 234
Operating lease term, month and year		2020-03
Sublease term, month and year		2020-03