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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Amount, after accumulated amortization, of debt premium.

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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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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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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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NOTES PAYABLE, FINANCE LEASES, AND COMMERCIAL BANK FINANCING - DSG Notes (Details) - USD ($)		3 Months Ended		4 Months Ended	9 Months Ended
	Jun. 10, 2020	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Gain on extinguishment of debt		$ 0	$ 0		$ 5,000,000	$ 0
Senior Notes \| DSG 6.625% Notes
Debt Instrument [Line Items]
Redeemed amount	$ 66,500,000			$ 15,000,000
Interest rate (as a percent)		6.625%			6.625%
Consideration				$ 10,000,000
Gain on extinguishment of debt					$ 5,000,000
Cash payments	10,000,000
Notes balance, net of deferred financing costs		$ 1,709,000,000			$ 1,709,000,000
Senior Notes \| DSG 12.750% Senior Secured Notes
Debt Instrument [Line Items]
Interest rate (as a percent)		12.75%			12.75%
Aggregate principal amount	31,000,000
Notes balance, net of deferred financing costs		$ 55,000,000			$ 55,000,000
Debt premium	$ 24,000,000
Redemption percentage					100.00%
Senior Notes \| 5.375% Senior Secured Notes due 2026
Debt Instrument [Line Items]
Interest rate (as a percent)		5.375%			5.375%
Redemption period one \| Senior Notes \| DSG 12.750% Senior Secured Notes
Debt Instrument [Line Items]
Redemption percentage					102.688%
Redemption period two \| Senior Notes \| DSG 12.750% Senior Secured Notes
Debt Instrument [Line Items]
Redemption percentage					101.344%
Redemption percentage of principal amount					40.00%
Redemption period three \| Senior Notes \| DSG 12.750% Senior Secured Notes
Debt Instrument [Line Items]
Redemption percentage					100.00%