Equity - Additional Information (Detail)	12 Months Ended
Dec. 31, 2020
Class A Common Stock [Member]
Class of Stock [Line Items]
Common stock, voting right	Class A common stock entitles the holder to one vote for each share
Class B Common Stock [Member]
Class of Stock [Line Items]
Common stock, voting right	Class B common stock entitles the holder to ten votes for each share
Common stock, conversion features	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.

Class A common stock entitles the holder to one vote for each share

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.