Other–Net, (Income) Expense (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Nonoperating Income (Expense) [Abstract]
Interest expense	$ 183.6	$ 120.3	$ 363.2	$ 223.1
Interest income	(37.3)	(46.0)	(83.1)	(80.2)
Net investment losses on equity securities (Note 7)	157.9	64.9	141.9	78.6
Retirement benefit plans	(114.4)	(115.6)	(230.5)	(231.4)
Other (income) expense	7.8	13.2	(21.0)	11.0
Other–net, (income) expense	$ 197.6	$ 36.8	$ 170.5	$ 1.1

Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of interest expense classified as nonoperating.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
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Amount of expense (reversal of expense) for net periodic benefit cost components, excluding service cost component, of defined benefit plan. Amount includes, but is not limited to, interest cost, expected (return) loss on plan asset, amortization of prior service cost (credit), amortization of (gain) loss, amortization of transition (asset) obligation, settlement (gain) loss, curtailment (gain) loss and certain termination benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Amount of income (expense) related to nonoperating activities, classified as other.

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