Impairments (Goodwill) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2020	Jun. 30, 2020
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment	$ 7,330	$ 7,330
Discounted Cash Flow \| Discount Rate \| Minimum
Finite-Lived Intangible Assets [Line Items]
Fair value inputs	9.00%
Discounted Cash Flow \| Discount Rate \| Maximum
Finite-Lived Intangible Assets [Line Items]
Fair value inputs	13.50%

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration