Dividends/Distributions - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Dividends [Abstract]
Dividends declared, per share	$ 0.50	$ 1.00	$ 0.96	$ 0.96	$ 1.50	$ 1.92	$ 3.84	$ 3.65	$ 3.32
Distributions paid, preferred stockholders	$ 91		$ 91		$ 182	$ 182	$ 365	$ 365	$ 365
Distributions paid, preferred stockholders, per share	$ 15.95		$ 15.95		$ 31.90	$ 31.90	$ 63.80	$ 79.75	$ 47.85
Distributions paid	$ 50,396		$ 96,039		$ 151,083	$ 191,954
Distributions paid, per share	$ 0.50		$ 0.96		$ 1.50	$ 1.92

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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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 preferred stock dividends declared with the form of settlement in cash.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 45
-Paragraph 2
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Aggregate dividends paid during the period for each share of preferred stock outstanding.

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