Stock-Based Compensation - Summary of Significant Ranges of Outstanding and Exercisable Options (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Aggregate Intrinsic Value		$ 100
Options | $1.57 - $14.99
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range limit (in dollars per share)	$ 1.57
Upper range limit (in dollars per share)	$ 14.99
Number Outstanding (in shares)	143
Weighted Average Remaining Contractual Life	8 years 3 months 3 days
Weighted Average Exercise Price (in dollars per share)	$ 2.62
Number Exercisable (in shares) | shares	68
Weighted Average Exercise Price (in dollars per share)	$ 2.94
Options Outstanding, Aggregate Intrinsic Value	$ 25
Options | $15.00 - $25.59
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range limit (in dollars per share)	$ 15.00
Upper range limit (in dollars per share)	$ 25.59
Number Outstanding (in shares)	8
Weighted Average Remaining Contractual Life	2 years 8 months 26 days
Weighted Average Exercise Price (in dollars per share)	$ 15.00
Number Exercisable (in shares) | shares	8
Weighted Average Exercise Price (in dollars per share)	$ 15.00
Options | $25.60 - $143.99
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range limit (in dollars per share)	25.60
Upper range limit (in dollars per share)	$ 143.99
Number Outstanding (in shares)	2
Weighted Average Remaining Contractual Life	3 years 4 months 6 days
Weighted Average Exercise Price (in dollars per share)	$ 41.81
Number Exercisable (in shares) | shares	2
Weighted Average Exercise Price (in dollars per share)	$ 41.81
Options | $144.00 - $409.99
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range limit (in dollars per share)	144.00
Upper range limit (in dollars per share)	$ 409.99
Number Outstanding (in shares)	5
Weighted Average Remaining Contractual Life	5 years 7 months 24 days
Weighted Average Exercise Price (in dollars per share)	$ 144.00
Number Exercisable (in shares) | shares	5
Weighted Average Exercise Price (in dollars per share)	$ 144.00
Options | $410.00 - $924.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range limit (in dollars per share)	410.0
Upper range limit (in dollars per share)	$ 924.00
Number Outstanding (in shares)	1
Weighted Average Remaining Contractual Life	4 years 2 months 8 days
Weighted Average Exercise Price (in dollars per share)	$ 430.64
Number Exercisable (in shares) | shares	1
Weighted Average Exercise Price (in dollars per share)	$ 430.64
Options | $1.57 - $924.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range limit (in dollars per share)	1.57
Upper range limit (in dollars per share)	$ 924.00
Number Outstanding (in shares)	159
Weighted Average Remaining Contractual Life	7 years 9 months 18 days
Weighted Average Exercise Price (in dollars per share)	$ 10.82
Number Exercisable (in shares) | shares	84
Weighted Average Exercise Price (in dollars per share)	$ 18.39
Options Outstanding, Aggregate Intrinsic Value	$ 25