DEBT - 2014 Revolving Credit Facility (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
2014 Revolving Credit Facility \| Letters of Credit
Debt
Aggregate letters of credit issued	$ 152	$ 165

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

No definition available.

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant