Equity - Summary of Class A Common Stock Issuances (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		6 Months Ended
	May 31, 2020	May 31, 2013	Jun. 30, 2020	Jun. 30, 2019
Class of Stock [Line Items]
Shares issued		25,875,000	10,841,667	10,535,181
Net proceeds			$ 278,322	$ 372,329
Shares issued, Wtd. Avg.			10,840,696
Gross share issue price, Wtd. Avg.			$ 27.79
Net share issue price, Wtd. Avg.			$ 27.52
Net proceeds,Wtd. Avg.			$ 297,599
Class A Common Stock [Member]
Class of Stock [Line Items]
Shares issued	840,696		10,000,000
Gross share issue price	$ 22.93		$ 28.20
Net share issue price	$ 22.93		$ 27.91
Net proceeds	$ 19,277		$ 278,322