DEBT - Senior Notes (Details) - Senior notes - USD ($)	6 Months Ended
Jun. 30, 2020	Mar. 31, 2020
Debt Instrument [Line Items]
Net proceeds from issuance of notes	$ 1,088,000,000
Redemption price, percentage	100.00%
$600 million, 4.50% due April 1, 2025
Debt Instrument [Line Items]
Face amount	$ 600,000,000	$ 600,000,000
Stated interest rate (percent)	4.50%	4.50%
$500 million, 4.875% due April 1, 2030]
Debt Instrument [Line Items]
Face amount	$ 500,000,000	$ 500,000,000
Stated interest rate (percent)	4.875%	4.875%
$250 million, 8.15% due June 15, 2038
Debt Instrument [Line Items]
Face amount	$ 250,000,000
Stated interest rate (percent)	8.15%

Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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