Acquisitions & Divestitures - 2020 Acquisitions (Details) - 2020 Acquisitions $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) item
Acquisitions
Number of acquisitions \| item	7
Aggregate acquisitions cost \| $	$ 723

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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