Equity - Schedule of Issued Shares of Class A common stock Under 2009 Long-Term Incentive Plan (Detail) - 2009 Long-Term Incentive Plan [Member] - Class A Common Stock [Member] - shares |
12 Months Ended | |
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Dec. 31, 2019 |
Dec. 31, 2018 |
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Independent Directors Compensation Plan [Member] | ||
Schedule Of Employee Incentive Compensation Plans Disclosures [Line Items] | ||
Shares issued to independent directors for services rendered, in lieu of cash compensation | 1,045 | |
Stock Option [Member] | ||
Schedule Of Employee Incentive Compensation Plans Disclosures [Line Items] | ||
Shares issued to employees upon exercise of stock options and employee stock purchase program | 38,260 | 45,800 |
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- Definition Schedule of employee incentive compensation plans disclosures. No definition available.
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- Definition Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders. No definition available.
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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