Dividends/Distributions - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Equity [Abstract]
Distributions paid	$ 75,818	$ 100,687
Cash dividends declared per share of common stock (in dollars per share)	$ 0.75	$ 1.00	$ 2.50	$ 3.84	$ 3.65
Dividends declared	$ 75,818	$ 100,687
Dividends paid (in dollars per share)	$ 0.75	$ 1.00
Dividends paid	$ 91	$ 91	$ 365	$ 365	$ 365
Distributions paid, preferred stockholders, per share	$ 15.95	$ 15.95	$ 63.80	$ 63.80	$ 79.75

Aggregate dividends paid during the period for each share of common stock outstanding.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

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Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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Aggregate dividends paid during the period for each share of preferred stock outstanding.

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