Fair Value Measurements - Summary of company's financial instruments that were measured at fair value by level within the fair value hierarchy on a recurring basis (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Fair Value By Fair Value Hierarchy Level [Line Items]
Financial Assets	$ 22,571	$ 12,093
Money market funds [Member]
Fair Value By Fair Value Hierarchy Level [Line Items]
Balance Sheet Location	Cash and cash equivalents	Cash and cash equivalents
Financial Assets	$ 477	$ 6,413
Marketable security [Member]
Fair Value By Fair Value Hierarchy Level [Line Items]
Balance Sheet Location	Prepaid expenses and other current assets
Financial Assets	$ 5,354
Embedded derivative [Member]
Fair Value By Fair Value Hierarchy Level [Line Items]
Balance Sheet Location	Long-term debt	Long-term debt
Financial Assets	$ 16,740	$ 5,680
Convertible security [Member]
Fair Value By Fair Value Hierarchy Level [Line Items]
Balance Sheet Location	Deferred acquisition costs, current	Deferred acquisition costs, current
Financial Liability	$ 47,200	$ 46,500
Level 1 [Member]
Fair Value By Fair Value Hierarchy Level [Line Items]
Financial Assets	5,831	6,413
Level 1 [Member] | Money market funds [Member]
Fair Value By Fair Value Hierarchy Level [Line Items]
Financial Assets	477	6,413
Level 1 [Member] | Marketable security [Member]
Fair Value By Fair Value Hierarchy Level [Line Items]
Financial Assets	5,354
Level 3 [Member]
Fair Value By Fair Value Hierarchy Level [Line Items]
Financial Assets	16,740	5,680
Level 3 [Member] | Embedded derivative [Member]
Fair Value By Fair Value Hierarchy Level [Line Items]
Financial Assets	16,740	5,680
Level 3 [Member] | Convertible security [Member]
Fair Value By Fair Value Hierarchy Level [Line Items]
Financial Liability	$ 47,200	$ 46,500