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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Goodwill and Other Intangible Assets - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Amortization of intangible assets		$ 40	$ 58	$ 58
Minimum
Goodwill [Line Items]
Expected amortization for the year 2020		37
Expected amortization for the year 2021		37
Expected amortization for the year 2022		37
Expected amortization for the year 2023		37
Maximum
Goodwill [Line Items]
Expected amortization for the year 2020		43
Expected amortization for the year 2021		43
Expected amortization for the year 2022		43
Expected amortization for the year 2023		$ 43
Disks Assets Group
Goodwill [Line Items]
Intangible asset impairments	$ 197