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

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NOTES PAYABLE AND COMMERCIAL BANK FINANCING - Schedule of Notes Payable, Capital Leases and Commercial Bank Financing (Details) - USD ($)		12 Months Ended
	Dec. 04, 2020	Dec. 31, 2020	Jun. 30, 2020	Jun. 10, 2020	Dec. 31, 2019	Nov. 27, 2019	Aug. 02, 2019
Debt Instrument [Line Items]
Outstanding debt amount		$ 12,696,000,000
Net carrying value of debt		12,734,000,000			$ 12,669,000,000
Finance leases		38,000,000			38,000,000
Less: Deferred financing costs and discount		(183,000,000)			(231,000,000)
Less: Current portion		(56,000,000)			(69,000,000)
Less: Finance leases - affiliate, current portion		(5,000,000)			(5,000,000)
Net carrying value of long-term debt		12,493,000,000			12,367,000,000
DSG Accounts Receivable Securitization Facility
Debt Instrument [Line Items]
Outstanding debt amount		177,000,000			0
Debt of variable interest entities
Debt Instrument [Line Items]
Outstanding debt amount		17,000,000			21,000,000
Debt of other non-media related subsidiaries
Debt Instrument [Line Items]
Outstanding debt amount		17,000,000			18,000,000
Finance leases
Debt Instrument [Line Items]
Finance leases		30,000,000			27,000,000
Finance leases - affiliate
Debt Instrument [Line Items]
Finance leases		8,000,000			11,000,000
Less: Finance leases - affiliate, current portion		(2,000,000)			(2,000,000)
Notes \| 6.125% Unsecured Notes due 2022
Debt Instrument [Line Items]
Interest rate						6.125%
Aggregate principal amount						$ 500,000,000
Notes \| 5.625% Senior Unsecured Notes due 2024
Debt Instrument [Line Items]
Outstanding debt amount		$ 0			550,000,000
Interest rate		5.625%
Aggregate principal amount	$ 550,000,000
Redeemed aggregate principal amount	$ 550,000,000
Prepayment of debt		$ 15,000,000
Notes \| 5.875% Senior Unsecured Notes due 2026
Debt Instrument [Line Items]
Outstanding debt amount		$ 348,000,000			350,000,000
Interest rate		5.875%
Notes \| 5.125% Senior Unsecured Notes due 2027
Debt Instrument [Line Items]
Outstanding debt amount		$ 400,000,000			400,000,000
Interest rate		5.125%
Notes \| 5.500% Unsecured Notes due 2030
Debt Instrument [Line Items]
Outstanding debt amount		$ 500,000,000			500,000,000
Interest rate		5.50%				5.50%
Aggregate principal amount						$ 500,000,000
Notes \| 4.125% Senior Secured Notes due 2030
Debt Instrument [Line Items]
Outstanding debt amount		$ 750,000,000			0
Interest rate	4.125%	4.125%
Aggregate principal amount	$ 750,000,000
Notes \| 12.750% Senior Secured Notes, due 2026
Debt Instrument [Line Items]
Outstanding debt amount		$ 31,000,000			0
Interest rate		12.75%
Aggregate principal amount		$ 31,000,000
Notes \| 5.375% Secured Notes due 2026
Debt Instrument [Line Items]
Outstanding debt amount		$ 3,050,000,000			3,050,000,000
Interest rate		5.375%					5.375%
Aggregate principal amount							$ 3,050,000,000
Notes \| 6.625% Unsecured Notes due 2027
Debt Instrument [Line Items]
Outstanding debt amount		$ 1,744,000,000			1,825,000,000
Interest rate		6.625%	6.625%
Aggregate principal amount				$ 31,000,000			$ 1,825,000,000
STG Term Loan Facility \| Term Loan \| Term Loan B-1
Debt Instrument [Line Items]
Outstanding debt amount		$ 1,119,000,000			1,329,000,000
Prepayment of debt	$ 200,000,000
STG Term Loan Facility \| Term Loan \| Term Loan B-2
Debt Instrument [Line Items]
Outstanding debt amount		1,284,000,000			1,297,000,000
DSG Term Loan \| Term Loan
Debt Instrument [Line Items]
Outstanding debt amount		$ 3,259,000,000			$ 3,291,000,000