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FAIR VALUE MEASUREMENTS (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jul. 01, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading equity securities gain or (loss)	$ 56	$ 8	$ 10
Fair value of debt	4,400	4,600
UMass Joint Venture
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Ownership percentage by noncontrolling owners				18.90%
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other than temporary impairment	$ 8
Level 3 \| Contingent Consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total (gains)/losses included in earnings - realized/unrealized		1
Level 3 \| Contingent Consideration \| Other Operating Income (Expense)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total (gains)/losses included in earnings - realized/unrealized		$ 1