Equity	12 Months Ended
Dec. 31, 2018
Equity [Abstract]
Equity	7. Equity On June 15, 2018, the Company effected an eight-for-one forward stock split of its issued and outstanding shares of common stock and a proportional adjustment to the existing conversion ratios for each series of the Company’s Preferred Stock. Accordingly, all share and per share amounts for all periods presented in the accompanying financial statements and notes thereto have been adjusted retroactively, where applicable, to reflect this stock split and adjustment of the preferred stock conversion ratios. In connection with the stock split, the Company effected an increase in the number of authorized common shares to 57,570,856 shares. On July 2, 2018, the Company completed its IPO, in which it issued and sold 3,125,000 shares of Class A common stock at a public offering price of $18.00 per share, resulting in net proceeds to the Company of approximately $48.6 million after deducting underwriting discounts and commissions and other offering costs. Upon closing of the IPO, the Company’s authorized shares of common stock were increased to 220,000,000 shares of Class A common stock and 30,000,000 shares of Class B common stock. The Company also authorized 10,000,000 shares of undesignated preferred stock. Each share of Class A common stock entitles the holder to one vote for each share on all matters submitted to a vote of the Company’s stockholders at all meetings of stockholders and written actions in lieu of meetings. Each share of Class B common stock entitles the holder to ten votes for each share on all matters submitted to a vote of the Company’s stockholders at all meetings of stockholders and written actions in lieu of meetings. Holders of both classes of common stock are entitled to receive dividends, when and if declared by the board of directors. Each share of Class B common stock is convertible into one share of Class A common stock at the option of the holder at any time. Automatic conversion shall occur upon the occurrence of a transfer of such share of Class B common stock or at the date and time, or the occurrence of an event, specified by a vote or written consent of the holders of a majority of the voting power of the then outstanding shares of Class B common stock. A transfer is described as a sale, assignment, transfer, conveyance, hypothecation or disposition of such share or any legal or beneficial interest in such share other than certain permitted transfers as described in the Restated Certificate of Incorporation, including a transfer to a holder of Preferred Stock. Each share of Class B common stock held by a stockholder shall automatically convert into one fully paid and non-assessable share of Class A common stock nine months after the death or incapacity of the holder of such Class B common stock. During the years ended December 31, 2018 and 2017, 4,116,404 shares and 24,000 shares, respectively, of Class B common stock were automatically converted to 4,116,404 shares and 24,000 shares, respectively of Class A common stock pursuant to transfers as described above. No additional consideration was paid or received by the Company in connection with these exchanges. During the year ended December 31, 2017, the Company repurchased 1,341,216 shares of its common stock at a price of $6.89 per share for a total cost of $9.2 million. The repurchases were pursuant to a tender offer made by the Company to its stockholders, including employee stockholders. The price paid by the Company at the settlement date of each tender was the estimated fair value of the Company’s common stock at such settlement date. The Company immediately retired all outstanding treasury shares after the repurchase of common stock. Acquisitions of treasury stock have been recorded at cost. Treasury stock held was reported as a deduction from stockholders’ deficit. When the treasury stock was retired, the carrying value of the treasury stock was allocated between additional paid-in capital and retained earnings. The portion allocated to additional paid-in capital was limited to the sum of (i) all additional paid-in capital arising from previous retirements and net gains on sales of treasury stock of the same issue and (ii) the pro rata portion of additional paid-in capital and voluntary transfers of retained earnings on the same issue. To date, the Company has not reissued any treasury stock.

7. Equity

On June 15, 2018, the Company effected an eight-for-one forward stock split of its issued and outstanding shares of common stock and a proportional adjustment to the existing conversion ratios for each series of the Company’s Preferred Stock. Accordingly, all share and per share amounts for all periods presented in the accompanying financial statements and notes thereto have been adjusted retroactively, where applicable, to reflect this stock split and adjustment of the preferred stock conversion ratios. In connection with the stock split, the Company effected an increase in the number of authorized common shares to 57,570,856 shares.

On July 2, 2018, the Company completed its IPO, in which it issued and sold 3,125,000 shares of Class A common stock at a public offering price of $18.00 per share, resulting in net proceeds to the Company of approximately $48.6 million after deducting underwriting discounts and commissions and other offering costs. Upon closing of the IPO, the Company’s authorized shares of common stock were increased to 220,000,000 shares of Class A common stock and 30,000,000 shares of Class B common stock. The Company also authorized 10,000,000 shares of undesignated preferred stock.

Each share of Class A common stock entitles the holder to one vote for each share on all matters submitted to a vote of the Company’s stockholders at all meetings of stockholders and written actions in lieu of meetings. Each share of Class B common stock entitles the holder to ten votes for each share on all matters submitted to a vote of the Company’s stockholders at all meetings of stockholders and written actions in lieu of meetings.

Holders of both classes of common stock are entitled to receive dividends, when and if declared by the board of directors.

Each share of Class B common stock is convertible into one share of Class A common stock at the option of the holder at any time. Automatic conversion shall occur upon the occurrence of a transfer of such share of Class B common stock or at the date and time, or the occurrence of an event, specified by a vote or written consent of the holders of a majority of the voting power of the then outstanding shares of Class B common stock. A transfer is described as a sale, assignment, transfer, conveyance, hypothecation or disposition of such share or any legal or beneficial interest in such share other than certain permitted transfers as described in the Restated Certificate of Incorporation, including a transfer to a holder of Preferred Stock. Each share of Class B common stock held by a stockholder shall automatically convert into one fully paid and non-assessable share of Class A common stock nine months after the death or incapacity of the holder of such Class B common stock.

During the years ended December 31, 2018 and 2017, 4,116,404 shares and 24,000 shares, respectively, of Class B common stock were automatically converted to 4,116,404 shares and 24,000 shares, respectively of Class A common stock pursuant to transfers as described above. No additional consideration was paid or received by the Company in connection with these exchanges.

During the year ended December 31, 2017, the Company repurchased 1,341,216 shares of its common stock at a price of $6.89 per share for a total cost of $9.2 million. The repurchases were pursuant to a tender offer made by the Company to its stockholders, including employee stockholders. The price paid by the Company at the settlement date of each tender was the estimated fair value of the Company’s common stock at such settlement date. The Company immediately retired all outstanding treasury shares after the repurchase of common stock.

Acquisitions of treasury stock have been recorded at cost. Treasury stock held was reported as a deduction from stockholders’ deficit. When the treasury stock was retired, the carrying value of the treasury stock was allocated between additional paid-in capital and retained earnings. The portion allocated to additional paid-in capital was limited to the sum of (i) all additional paid-in capital arising from previous retirements and net gains on sales of treasury stock of the same issue and (ii) the pro rata portion of additional paid-in capital and voluntary transfers of retained earnings on the same issue. To date, the Company has not reissued any treasury stock.