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

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Debt Instrument, Prepayment Premium, Percent

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Debt Instrument, Quarterly Aggregate Payment, Percent

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Amount of short-term and long-term debt and lease obligation.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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 borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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NOTES PAYABLE AND COMMERCIAL BANK FINANCING - STG Bank Credit Agreement (Details) - USD ($)				3 Months Ended
	Aug. 23, 2019	Aug. 13, 2019	Apr. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Loss on extinguishment of debt				$ 2,000,000
Balance, net				12,463,000,000
Term Loan \| Term Loan B-2
Debt Instrument [Line Items]
Prepayment premium, percent	1.00%
Quarterly payment, percent	1.00%
Balance, net				1,279,000,000
Term Loan \| Term Loan B-2b
Debt Instrument [Line Items]
Debt term		7 years
Debt issued		$ 600,000,000
Debt discount		3,000,000
Term Loan \| Term Loan B-2a
Debt Instrument [Line Items]
Debt term	7 years
Debt issued	$ 700,000,000
Debt discount	$ 4,000,000
Term Loan \| Term Loan A-2
Debt Instrument [Line Items]
Repayment of remaining principal balance			$ 92,000,000
Senior Notes \| 5.375% Senior Unsecured Notes due 2021
Debt Instrument [Line Items]
Repayments of debt		$ 600,000,000
Interest rate (as a percent)		5.375%			5.375%
STG Revolving Credit Facility
Debt Instrument [Line Items]
Debt term	5 years
Maximum borrowing capacity	$ 650,000,000
Borrowings outstanding				0
Letters of credit				1,000,000
Available borrowing capacity				$ 649,000,000
Percent of borrowings exceeding total commitments	35.00%
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
LIBOR \| Term Loan \| Term Loan B-2b
Debt Instrument [Line Items]
Basis spread on variable rate		2.50%
LIBOR \| Term Loan \| Term Loan B-2a
Debt Instrument [Line Items]
Basis spread on variable rate	2.50%
LIBOR \| STG Revolving Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%