Commitments and Contingencies (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Unconditional Purchase Obligation [Line Items]
Purchase Obligation	$ 189,259
Rent expenses for operating leases	$ 94	$ 95	$ 100

Describes each unconditional purchase obligation (recorded and unrecorded) arrangement to purchase goods and services that extend over multiple periods, any assets pledged to secure payment, and the fixed or determinable amount of payments due in each of the next five years and thereafter. Also includes contractual obligations.

No definition available.

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