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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 |

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- Definition The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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