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LEASES - Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ (840.3)	$ (935.0)
Non-cash items:
New operating leases	138.5	135.6
Operating lease modifications and reassessments	324.8	818.1
Reduction of operating lease liability due to the ATC TIPL Transaction	0.0	(766.4)
Increase to operating lease right-of-use asset	8,420.1		$ 8,089.6
Increase to operating lease liability	$ 7,772.3		$ 7,452.3
Service Life
Non-cash items:
Increase to operating lease right-of-use asset		515.0
Increase to operating lease liability		$ 515.0

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Cash Flow, Lessee [Abstract]

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Disposal Group, Including Discontinued Operation, Reduction Of Operating Lease Liabilities

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Non-Cash Items [Abstract]

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Non-Cash Operating And Financing, Lease Modifications

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-1

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-5

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-Publisher FASB
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Amount of lessee's right to use underlying asset under operating lease.

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-Section 45
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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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-Topic 842
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