Capital Stock - Additional Information (Detail) - $ / shares	Apr. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Mar. 30, 2016	Oct. 01, 2013
Capital Unit [Line Items]
Common Stock, authorized shares	500,000,000	500,000,000	500,000,000	150,000,000	100,000,000
Common Stock, par value		$ 0.01	$ 0.01		$ 0.01
Preferred Stock, shares authorized	10,000,000
Common Stock, shares issued	24,150,000	148,571,412	144,386,618
Common Stock, shares outstanding		148,571,412	144,386,618
IPO [Member]
Capital Unit [Line Items]
Shares issued, price per share	$ 22.00
Private Placement [Member]
Capital Unit [Line Items]
Shares issued, price per share	$ 22.00
Shares issued	4,545,455
Junior Convertible Participating Preferred Stock [Member]
Capital Unit [Line Items]
Preferred Stock, shares authorized					70,000,000
Preferred Stock, par value					$ 0.01
Senior Convertible Participating Preferred Stock [Member]
Capital Unit [Line Items]
Preferred Stock, shares authorized				70,000,000
Preferred Stock, par value				$ 0.01