Earnings Per Share and Weighted-Average Shares Outstanding - Calculation of Basic Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Basic earnings per share
Net income available to common stockholders	[1]	$ 70,281	$ 104,406	$ 101,641
Basic weighted-average shares of common stock outstanding (in shares)		179,106	177,774	157,256
Basic earnings per share (in usd per share)		$ 0.39	$ 0.59	$ 0.65

[1] Includes a reduction for dividends on preferred stock or exchangeable preferred partnership units in the amount of $9.8 million, $12.9 million and $5.1 million for the years ended December 31, 2020, 2019 and 2018, respectively.