Debt Instrument, Covenant, First Lien Leverage Ratio Test, Borrowings Exceed Total Commitments, Percent

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Debt Instrument, Covenant, Required Prepayment, First Lien Leverage Ratio

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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Percentage of principal amount of debt redeemed.

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Fair value amount of debt instrument that was repurchased.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount, after accumulated amortization, of debt discount.

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Gross amount of debt extinguished.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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NOTES PAYABLE AND COMMERCIAL BANK FINANCING - STG Bank Credit Agreement and Notes (Details) - USD ($)								12 Months Ended
	Dec. 04, 2020	May 21, 2020	Mar. 17, 2020	Nov. 27, 2019	Aug. 23, 2019	Aug. 13, 2019	Aug. 02, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt								$ (10,000,000)	$ (10,000,000)	$ 0
Percent of borrowings exceeding total commitments								35.00%
Term Loan \| Term Loan B-2b
Debt Instrument [Line Items]
Debt term						7 years
Aggregate principal amount						$ 600,000,000
Unamortized debt discount						$ 3,000,000
Term Loan \| Term Loan B-2b \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate						2.50%
Term Loan \| Term Loan B-2a
Debt Instrument [Line Items]
Debt term					7 years
Aggregate principal amount					$ 700,000,000
Unamortized debt discount					$ 4,000,000
Term Loan \| Term Loan B-2a \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate					2.50%
Term Loan \| Term Loan B-2
Debt Instrument [Line Items]
Quarterly payment, percent					1.00%
Notes \| STG 6.125% Senior Unsecured Notes
Debt Instrument [Line Items]
Aggregate principal amount				$ 500,000,000
Interest rate				6.125%
Gain (loss) on extinguishment of debt								$ (8,000,000)
Amount extinguished								$ 510,000,000
Notes \| 5.375% Unsecured Notes due 2021
Debt Instrument [Line Items]
Repayments of debt						$ 600,000,000
Interest rate								5.375%
Gain (loss) on extinguishment of debt								$ (2,000,000)
Notes \| STG 5.625% Unsecured Notes
Debt Instrument [Line Items]
Aggregate principal amount	$ 550,000,000
Interest rate								5.625%
Amount extinguished	571,000,000
Consideration for debt								$ 550,000,000
Prepayment of debt								$ 15,000,000
Notes \| STG 5.875% Unsecured Notes
Debt Instrument [Line Items]
Interest rate								5.875%
Gain (loss) on extinguishment of debt								$ 200,000
Amount extinguished		$ 2,500,000
Consideration for debt		$ 2,300,000
Notes \| STG Notes \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Percentage of principal amount redeemed								35.00%
Notes \| STG Notes \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Percentage of principal amount redeemed								100.00%
Notes \| 5.500% Unsecured Notes due 2030
Debt Instrument [Line Items]
Aggregate principal amount				$ 500,000,000
Interest rate				5.50%				5.50%
Notes \| 5.500% Unsecured Notes due 2030 \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Debt instrument, redemption price (as a percent)				100.00%
Percentage of principal amount redeemed				40.00%
Notes \| 5.500% Unsecured Notes due 2030 \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Debt instrument, redemption price (as a percent)				102.75%
Notes \| 5.500% Unsecured Notes due 2030 \| Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Debt instrument, redemption price (as a percent)				101.833%
Notes \| 5.500% Unsecured Notes due 2030 \| Debt Instrument, Redemption, Period Four
Debt Instrument [Line Items]
Debt instrument, redemption price (as a percent)				100.917%
Notes \| 5.500% Unsecured Notes due 2030 \| Debt Instrument, Redemption, Period Five
Debt Instrument [Line Items]
Debt instrument, redemption price (as a percent)				100.00%
Notes \| STG 5.125% Unsecured Notes
Debt Instrument [Line Items]
Interest rate								5.125%
Notes \| 5.375% Secured Notes due 2026
Debt Instrument [Line Items]
Aggregate principal amount							$ 3,050,000,000
Interest rate							5.375%	5.375%
Notes \| 5.375% Secured Notes due 2026 \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Debt instrument, redemption price (as a percent)							102.688%
Notes \| 5.375% Secured Notes due 2026 \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Debt instrument, redemption price (as a percent)							101.344%
Notes \| 5.375% Secured Notes due 2026 \| Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Debt instrument, redemption price (as a percent)							100.00%
Notes \| 4.125% Senior Secured Notes due 2030
Debt Instrument [Line Items]
Aggregate principal amount	$ 750,000,000
Interest rate	4.125%							4.125%
Amount extinguished	$ 750,000,000
Debt instrument, redemption price (as a percent)								100.00%
Notes \| 4.125% Senior Secured Notes due 2030 \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Percentage of principal amount redeemed				40.00%
Notes \| 4.125% Senior Secured Notes due 2030 \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Debt instrument, redemption price (as a percent)				102.063%
Notes \| 4.125% Senior Secured Notes due 2030 \| Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Debt instrument, redemption price (as a percent)				101.375%
Notes \| 4.125% Senior Secured Notes due 2030 \| Debt Instrument, Redemption, Period Four
Debt Instrument [Line Items]
Debt instrument, redemption price (as a percent)				100.688%
Notes \| 4.125% Senior Secured Notes due 2030 \| Debt Instrument, Redemption, Period Five
Debt Instrument [Line Items]
Debt instrument, redemption price (as a percent)				100.00%
STG Revolving Credit Facility
Debt Instrument [Line Items]
Debt term					5 years
Amount drawn from credit facility			$ 648,000,000
Percent of borrowings exceeding total commitments					35.00%
First lien leverage ratio								4.5
STG Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate					2.00%
STG Revolving Credit Facility \| Line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity								$ 650,000,000
STG Revolving Credit Facility \| Line of credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate								2.00%
STG Letters of Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity					$ 50,000,000
STG Swingline Loans Facility
Debt Instrument [Line Items]
Maximum borrowing capacity					$ 50,000,000
DSG Revolving Credit Facility
Debt Instrument [Line Items]
Debt term					5 years
Maximum borrowing capacity					$ 650,000,000
Percent of borrowings exceeding total commitments					35.00%
First lien leverage ratio								6.25
DSG Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate					3.00%
DSG Revolving Credit Facility \| Line of credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate								3.00%
STG Term Loan Facility \| Term Loan \| Term Loan B-2 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate								2.50%
STG Term Loan Facility \| Term Loan \| Term Loan B-1
Debt Instrument [Line Items]
Prepayment of debt	$ 200,000,000
STG Term Loan Facility \| Term Loan \| Term Loan B-1 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate								2.25%