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Stock-Based Compensation - Summary of Stock Options Outstanding (Details) | 12 Months Ended
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Dec. 31, 2020 $ / shares shares
Options Outstanding, Number | shares | 4,624,725
Options Exercisable, Number | shares | 3,351,086
Exercise Price One [Member] |
Range of Exercise Prices, Upper | $ 2.00
Options Outstanding, Number | shares | 429,667
Options Outstanding, Weighted Average Remaining Contractual Term (in years) | 8 years 9 months 18 days
Options Outstanding, Weighted Average Exercise Price | $ 1.64
Options Exercisable, Number | shares | 147,276
Options Exercisable, Weighted Average Remaining Contractual Term (in years) | 8 years 9 months 18 days
Options Exercisable, Weighted Average Exercise Price | $ 1.66
Exercise Price Two [Member] |
Range of Exercise Prices, Upper | 2.00
Range of Exercise Prices, Lower | $ 5.00
Options Outstanding, Number | shares | 4,130,723
Options Outstanding, Weighted Average Remaining Contractual Term (in years) | 7 years 8 months 12 days
Options Outstanding, Weighted Average Exercise Price | $ 2.64
Options Exercisable, Number | shares | 3,139,475
Options Exercisable, Weighted Average Remaining Contractual Term (in years) | 7 years 3 months 19 days
Options Exercisable, Weighted Average Exercise Price | $ 2.53
Exercise Price Three [Member] |
Range of Exercise Prices, Upper | 81.90
Range of Exercise Prices, Lower | $ 5.00
Options Outstanding, Number | shares | 64,335
Options Outstanding, Weighted Average Remaining Contractual Term (in years) | 5 years 2 months 12 days
Options Outstanding, Weighted Average Exercise Price | $ 18.81
Options Exercisable, Number | shares | 64,335
Options Exercisable, Weighted Average Remaining Contractual Term (in years) | 5 years 2 months 12 days
Options Exercisable, Weighted Average Exercise Price | $ 18.81

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- Definition The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan. + 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)(1)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. + 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)(1)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Number of options outstanding, including both vested and non-vested options. + 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 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. + 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)(1)(i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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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 Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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