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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SIGNIFICANT ACCOUNTING POLICIES - Other Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Total amortization expense related to other intangible assets during the last three years and future estimated amortization
Total amortization expense related to other intangible assets	$ 219	$ 206	$ 193
2021	223
2022	219
2023	214
2024	207
2025	$ 200
Customer relationships
Other intangible assets
Weighted-average useful life of other amortizable assets	14 years
Trademarks
Other intangible assets
Weighted-average useful life of other amortizable assets	14 years
Patents
Other intangible assets
Weighted-average useful life of other amortizable assets	15 years
Other technology
Other intangible assets
Weighted-average useful life of other amortizable assets	7 years
Other intangibles
Other intangible assets
Weighted-average useful life of other amortizable assets	14 years	14 years