Other - Net, (Income) Expense (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Nonoperating Income (Expense) [Abstract]
Interest expense	$ 69.4	$ 61.9	$ 193.9	$ 162.1
Interest income	(32.1)	(45.1)	(118.8)	(114.6)
Retirement benefit	(62.9)	(63.8)	(174.2)	(191.3)
Other income	41.0	(2.9)	9.0	(44.8)
Other–net, (income) expense	$ 15.4	$ (49.9)	$ (90.1)	$ (188.6)

Amount of the cost of borrowed funds accounted for as interest expense.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-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

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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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