Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount, after accumulated amortization, of right-of-use asset from finance lease.

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Amount of gain (loss) on sale and leaseback transaction from transfer of asset accounted for as sale.

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Leases - Sale and Leased-backed asset and obligation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Mar. 31, 2019
Property, Plant and Equipment [Line Items]
Finance lease asset		$ 106	$ 119	$ 10
Finance lease obligation		$ 100	$ 115
Gain on sale leaseback transactions, net	$ 82
Constructed machinery and equipment \| Municipal securities
Property, Plant and Equipment [Line Items]
Finance lease asset					$ 9
Finance lease obligation				$ 10	$ 9