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v3.20.4

Share-based Compensation (Details) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) award_type shares | Dec. 31, 2019 USD ($)
Amended and Restated Stock Option Plan [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Shares authorized (shares) | 12,900,000 |
Shares remaining (shares) | 5,082,695 |
Share based compensation, vesting rights (in time period) | 3 years |
Amended and Restated Stock Option Plan [Member] | Non-employee director [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share based compensation, vesting rights (in time period) | 12 months |
Long Term Incentive Plan [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share based compensation, vesting rights (in time period) | 3 years |
Number of award types provided | award_type | 2 |
Performance unit liability | $ | $ 6.5 | $ 3.7

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- Definition Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date. + References No definition available. + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + 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 (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Number of shares authorized for issuance under share-based payment arrangement. + 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 (a)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + 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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