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Share-Based Compensation - Fully-vested Common Stock Issued to Non-employee Directors (Details) - Common Stock - Non-employee Directors shares in Thousands, $ in Thousands | 9 Months Ended
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Sep. 30, 2021 USD ($) director shares | Sep. 30, 2020 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Number of non-employee directors to whom fully vested common stock is granted | director | 6 |
Awards issued (in shares) | shares | 51 | 68
Grant date fair value of awards issued | $ | $ 525 | $ 326

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- Definition Represents the number of non-employee directors to whom fully vested common stock is granted. + References No definition available. + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Number of shares issued 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 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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