Dividends/Distributions - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2017
Dividends [Line Items]
Dividends declared								$ 269,502	$ 81,534
Dividends declared, per share	$ 0.96	$ 0.96	$ 0.96	$ 0.91	$ 0.91	$ 0.91	$ 2.88	$ 2.73	$ 0.83
Distributions paid, preferred stockholders	$ 91			$ 91			$ 273	$ 364
Distributions paid, preferred stockholders, per share	$ 15.95			$ 15.95			$ 47.85	$ 63.80
Distributions paid	$ 96,390			$ 90,177			$ 288,344	$ 351,036
Distributions paid, per share	$ 0.96			$ 0.91			$ 2.88	$ 3.56

Dividends [Line Items]

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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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.

+ References

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

+ References

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