Acquisitions & Divestitures - 2020 Acquisitions (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) item	Dec. 31, 2021 USD ($)
Acquisitions
Restricted Cash	$ 463	$ 307
2020 Acquisitions
Acquisitions
Number of acquisitions \| item	7
Aggregate acquisitions cost	$ 723
Restricted Cash	$ 323

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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- Definition

The number of businesses acquired by the entity during the period.

+ References

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=123431023&loc=SL98516268-108586

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-Name Accounting Standards Codification
-Topic 942
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-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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