Summary of Significant Accounting Policies - Credit loss (Details) - USD ($) $ in Millions		12 Months Ended
Nov. 04, 2024	Dec. 31, 2024	Dec. 31, 2023
Allowance activity
Allowance for doubtful accounts, beginning balance		$ 30	$ 26
Additions charged to expense		65	53
Accounts written-off, net of recoveries		(55)	(58)
Acquisitions, divestitures and other, net		125	9
Allowance for doubtful accounts, ending balance		$ 165	$ 30
Receivables outstanding less than 60 days (as a percent)		85.00%	90.00%
Threshold period to measure receivables		60 days
Receivables related to income tax		$ 255	$ 120
Federal natural gas fuel credits receivable		$ 46	$ 26
Receivables classified as current (as a percent)		0.65%	0.50%
Stericycle [Member]
Allowance activity
Acquisitions, divestitures and other, net	$ 130

Amount of allowance for credit loss on accounts receivable, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(4))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-4

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(4))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(5))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

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- Definition

Amount of other increase (decrease) to the allowance for credit loss.

+ References

No definition available.

+ Details

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- Definition

The amount of federal natural gas fuel credits receivable.

+ References

No definition available.

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- Definition

The percentage of other receivables classified as current assets.

+ References

No definition available.

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- Definition

The percentage of receivables outstanding less than threshold period.

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No definition available.

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- Definition

The threshold period used to measure receivables.

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