Long-term Debt and Finance Leases - Issuance of Convertible Senior Notes (Details) - Convertible Senior Notes Due 2048 - Recourse Debt $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($) $ / shares	Dec. 31, 2020 USD ($) $ / shares
Debt Instrument [Line Items]
Conversion price per common share (in usd per share) \| $ / shares	$ 44.89	$ 46.24
Conversion ratio	0.0222761	0.0216242
Carrying amount of equity component \| $	$ 518	$ 503

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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The price per share of the conversion feature embedded in the debt instrument.

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