The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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INTANGIBLE ASSETS AND GOODWILL - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Impairment of intangible assets		$ 64
Expected aggregate future amortization expense of intangible assets for 2022	$ 163
Expected aggregate future amortization expense of intangible assets for 2023	147
Expected aggregate future amortization expense of intangible assets for 2024	134
Expected aggregate future amortization expense of intangible assets for 2025	122
Expected aggregate future amortization expense of intangible assets for 2026	$ 110
Minimum
Finite-Lived Intangible Assets [Line Items]
Range of amortization life of intangible assets	15 years
Maximum
Finite-Lived Intangible Assets [Line Items]
Range of amortization life of intangible assets	30 years
Contracts acquired in business combinations and other
Finite-Lived Intangible Assets [Line Items]
Amortization expense of intangible assets	$ 165	97	$ 105
Contracts acquired in business combinations and other \| Reimbursed Expenses
Finite-Lived Intangible Assets [Line Items]
Amortization expense of intangible assets	$ 62	$ 0	$ 0