CAPITAL STOCK - Summary of Dividend Distribution Activity (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Dividends Payable [Line Items]
Dividends and dividend equivalents declared on common stock and share-based awards	$ 309,972,000	$ 364,266,000	$ 667,791,000	$ 798,893,000
Distributions declared per common share (in dollars per share)	$ 0.22	$ 0.25	$ 0.47	$ 0.55
Distributions paid to common stockholders after period end	$ 309,686,000	$ 364,066,000	$ 309,686,000	$ 364,066,000
Distributions paid per common share after period end (in dollars per share)	$ 0.22	$ 0.25	$ 0.22	$ 0.25
Series C
Dividends Payable [Line Items]
Preferred dividends declared	$ 0	$ 3,336,000	$ 0	$ 6,672,000
Preferred series dividends declared (in dollars per share)	$ 0	$ 0.477	$ 0	$ 0.953
Series D
Dividends Payable [Line Items]
Preferred dividends declared	$ 8,625,000	$ 8,625,000	$ 17,250,000	$ 17,250,000
Preferred series dividends declared (in dollars per share)	$ 0.469	$ 0.469	$ 0.938	$ 0.938
Series F
Dividends Payable [Line Items]
Preferred dividends declared	$ 12,510,000	$ 12,510,000	$ 25,020,000	$ 25,020,000
Preferred series dividends declared (in dollars per share)	$ 0.434	$ 0.434	$ 0.869	$ 0.868
Series G
Dividends Payable [Line Items]
Preferred dividends declared	$ 6,906,000	$ 6,906,000	$ 13,812,000	$ 13,812,000
Preferred series dividends declared (in dollars per share)	$ 0.406	$ 0.406	$ 0.813	$ 0.813
Series H
Dividends Payable [Line Items]
Preferred dividends declared	$ 0	$ 745,000	$ 0	$ 1,862,000
Preferred series dividends declared (in dollars per share)	$ 0	$ 0.339	$ 0	$ 0.846
Series I
Dividends Payable [Line Items]
Preferred dividends declared	$ 7,468,000	$ 0	$ 14,936,000	$ 0
Preferred series dividends declared (in dollars per share)	$ 0.422	$ 0	$ 0.844	$ 0

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

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