SUBSEQUENT EVENTS (Details)				1 Months Ended		3 Months Ended
	May 06, 2021 USD ($) $ / shares	Mar. 30, 2021	Mar. 30, 2020	May 07, 2021 item	May 06, 2021 USD ($) shares	Mar. 31, 2021 USD ($) shares	Mar. 31, 2020 shares
Subsequent Event [Line Items]
Date dividends declared		Feb. 16, 2021	Feb. 12, 2020
Date dividends paid		Mar. 30, 2021	Mar. 30, 2020
Date of record		Mar. 16, 2021	Mar. 16, 2020
Shares repurchased | shares						8,032,171	12,000,000
Aggregate remaining authorization amount of common Stock share repurchase						$ 1,100,000,000
Three consolidated investment entities related to securitized portfolios of certain debt securities
Subsequent Event [Line Items]
Carrying value of senior notes						100,000,000
Payments related to guarantees						0
Consolidated investment entity related to securitized portfolios of certain debt securities
Subsequent Event [Line Items]
Number of investment entities | item				1
Carrying value of senior notes						$ 25,000,000
Subsequent event
Subsequent Event [Line Items]
Dividends declared per common share | $ / shares	$ 0.32
Dividends declared per preferred share | $ / shares	$ 365.625
Shares repurchased | shares					1,000,000
Aggregate purchase price of repurchased shares					$ 65,000,000
Aggregate remaining authorization amount of common Stock share repurchase	$ 1,100,000,000				$ 1,100,000,000
Subsequent event | Disposed of by Means Other than Sale
Subsequent Event [Line Items]
Number of investment entities | item				3
Subsequent event | Common Stock
Subsequent Event [Line Items]
Date dividends declared	May 06, 2021
Date dividends paid	Jun. 29, 2021
Date of record	Jun. 15, 2021
Subsequent event | Preferred Stock
Subsequent Event [Line Items]
Date dividends declared	May 06, 2021
Date dividends paid	Jun. 15, 2021
Date of record	May 31, 2021