CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net Income	$ 615.9	$ 568.6	$ 743.4
Other comprehensive income, net of tax:
Foreign exchange translation adjustments	5.7	(10.6)	18.4
Defined benefit plan adjustments gain (loss)	(0.9)	1.4	12.6
Income (loss) from derivative agreements	(17.9)	(7.4)	(3.6)
Other comprehensive (loss) income	(13.1)	(16.6)	27.4
Comprehensive income	$ 602.8	$ 552.0	$ 770.8

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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