Equity - Class A Common Stock (Detail) - Class A Common Stock - shares |
1 Months Ended | ||||||||
|---|---|---|---|---|---|---|---|---|---|
Nov. 30, 2017 |
Aug. 31, 2017 |
May 31, 2017 |
Apr. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
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| Class Of Stock [Line Items] | |||||||||
| Common stock, shares outstanding | 8,142,120 | 8,074,197 | 7,990,000 | 7,768,000 | |||||
| Issuance of Class A common Stock upon conversion of Class B units to Class A common stock | 10,900 | 24,119 | 2,000 | 26,008 | |||||
| Issuance of Class B shares, Shares | 3,896 | 1,000 | |||||||
| Common stock conversion date | Nov. 30, 2017 | Aug. 31, 2017 | May 31, 2017 | Mar. 31, 2017 | |||||
| Stock issued upon vesting of stock units | 2017-05 | 2017-04 | |||||||
| X | ||||||||||
- Definition Common stock conversion date. No definition available.
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- Definition Sale of stock transaction period month and year. No definition available.
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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. No definition available.
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- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of new stock issued during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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