Development and License Agreements - Summary of Prepaid R&D Asset and Manufacturing Efficiency Asset (Detail) - USD ($) $ in Thousands		Sep. 30, 2019	Dec. 31, 2018
Other current assets
Deferred Costs Capitalized Prepaid And Other Assets [Line Items]
Prepaid R&D asset	[1]	$ 52	$ 47
Other assets
Deferred Costs Capitalized Prepaid And Other Assets [Line Items]
Prepaid R&D asset	[2]	2,096	2,156
Manufacturing efficiency asset	[2]	$ 1,410	$ 1,594

[1] Included in “Other current assets” in the Company's condensed consolidated balance sheets.

[2] Included in “Other assets” in the Company's condensed consolidated balance sheets