Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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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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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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- Definition

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

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The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

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DEBT AND CREDIT FACILITIES - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended
	Mar. 31, 2021	Jan. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Repayments of long-term debt			$ 1,250,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Amounts outstanding under revolving credit facilities	$ 0		0	$ 0
Revolving Credit Facility \| the "2020 Revolving Credit Facility"
Debt Instrument [Line Items]
Maximum borrowing capacity	2,500,000,000		2,500,000,000
Senior Notes \| the "2014 Senior Notes"
Debt Instrument [Line Items]
Repayments of senior unsecured notes		$ 1,000,000,000.0
Medium-term Notes \| Three-Year Senior Term Loan Facility
Debt Instrument [Line Items]
Repayments of senior unsecured notes	$ 250,000,000
Contractual term	3 years
Maximum borrowing capacity	$ 1,000,000,000.0		1,000,000,000.0
Remaining outstanding	$ 750,000,000		$ 750,000,000