Other Assets - Equity Method Investments and Leases - Equity Method Investments (Details) - IM - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Equity Method Investments
Investments		$ 2,214	$ 2,410
Income (loss)		$ 104	$ 0	$ (81)
Impairment of equity method investment	$ 41

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Data Type:	xbrli:monetaryItemType
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