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Stock-Based Compensation - Additional Information (Detail) - 2007 Plan [Member] $ in Millions | 12 Months Ended
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Dec. 31, 2020 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Total unrecognized compensation cost for restricted stock granted | $ | $ 1.2
Cost expected to be recognized over a weighted-average period | 2 years 9 months 18 days
Minimum [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Restricted stock units and restricted stock awards, vest, period | 1 year
Maximum [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Restricted stock units and restricted stock awards, vest, period | 5 years
Class A Common Stock [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Shares authorized | shares | 7,500,000

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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents 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 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + 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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