Other Comprehensive Income (Loss) (AOCI) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			$ 10,775.4
Other comprehensive income (loss) before reclassifications	$ (26.7)	$ (122.4)	50.1	$ (65.9)
Net amount reclassified from accumulated other comprehensive loss	15.3	60.0	5.8	121.3
Net other comprehensive income (loss)	(11.4)	(62.4)	55.9	55.4
Ending balance	11,149.3		11,149.3
Accumulated Other Comprehensive Loss
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(3,777.3)	(4,225.3)	(3,844.6)	(4,343.1)
Ending balance	(3,788.7)	(4,287.7)	(3,788.7)	(4,287.7)
Foreign Currency Translation Gains (Losses)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(1,826.6)	(1,575.2)	(1,874.2)	(1,550.2)
Other comprehensive income (loss) before reclassifications	(58.7)	(269.6)	14.1	(294.6)
Net amount reclassified from accumulated other comprehensive loss	0.0	0.6	(25.2)	0.6
Net other comprehensive income (loss)	(58.7)	(269.0)	(11.1)	(294.0)
Ending balance	(1,885.3)	(1,844.2)	(1,885.3)	(1,844.2)
Net Unrealized Gains (Losses) on Available-For-Sale Securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(28.3)	(18.1)	(37.1)	3.7
Other comprehensive income (loss) before reclassifications	(5.9)	(9.3)	2.2	(30.6)
Net amount reclassified from accumulated other comprehensive loss	0.7	(0.5)	1.4	(1.0)
Net other comprehensive income (loss)	(5.2)	(9.8)	3.6	(31.6)
Ending balance	(33.5)	(27.9)	(33.5)	(27.9)
Defined Benefit Pension and Retiree Health Benefit Plans
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(2,066.1)	(2,531.6)	(2,062.3)	(2,583.6)
Other comprehensive income (loss) before reclassifications	(5.6)	31.7	(22.4)	25.1
Net amount reclassified from accumulated other comprehensive loss	12.9	56.7	25.9	115.3
Net other comprehensive income (loss)	7.3	88.4	3.5	140.4
Ending balance	(2,058.8)	(2,443.2)	(2,058.8)	(2,443.2)
Net unrealized gains/losses on cash flow hedges
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	143.7	(100.4)	129.0	(213.0)
Other comprehensive income (loss) before reclassifications	43.5	124.8	56.2	234.2
Net amount reclassified from accumulated other comprehensive loss	1.7	3.2	3.7	6.4
Net other comprehensive income (loss)	45.2	128.0	59.9	240.6
Ending balance	$ 188.9	$ 27.6	$ 188.9	$ 27.6