Goodwill and Intangible Assets - Schedule of Finite-Lived and Indefinite-Lived Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023
Finite-lived Intangible Assets [Roll Forward]
Amortization	$ (95.8)	$ (99.0)	$ (103.9)	$ (106.7)
Other indefinite-lived intangibles
Balance at beginning of period	1,280.0	1,280.0	1,280.0	1,280.0
Additions at cost	0.0	0.0	0.0	0.0
Other	0.0	0.0	0.0	0.0
Balance at end of period	1,280.0	1,280.0	1,280.0	1,280.0
Total
Balance at beginning of period	3,805.2	3,915.9	4,218.6	4,320.1
Additions at cost	0.3	0.1	0.1	0.1
Amortization	(95.8)	(99.0)	(103.9)	(106.7)
Other	(0.1)	(11.8)	(1.5)	5.1
Balance at end of period	3,709.6	3,805.2	4,113.3	4,218.6
Customer relationships
Finite-lived Intangible Assets [Roll Forward]
Balance at beginning of period	1,261.7	1,316.7	1,481.0	1,536.7
Additions at cost	0.0	0.0	0.0	0.0
Amortization	(50.5)	(52.4)	(55.1)	(56.8)
Other	0.3	(2.6)	(1.5)	1.1
Balance at end of period	1,211.5	1,261.7	1,424.4	1,481.0
Total
Amortization	(50.5)	(52.4)	(55.1)	(56.8)
Reacquired rights
Finite-lived Intangible Assets [Roll Forward]
Balance at beginning of period	222.8	233.9	243.6	245.5
Additions at cost	0.0	0.0	0.0	0.0
Amortization	(4.7)	(4.8)	(4.8)	(4.7)
Other	(0.7)	(6.3)	0.0	2.8
Balance at end of period	217.4	222.8	238.8	243.6
Total
Amortization	(4.7)	(4.8)	(4.8)	(4.7)
Database
Finite-lived Intangible Assets [Roll Forward]
Balance at beginning of period	900.5	940.6	1,059.1	1,100.0
Additions at cost	0.0	0.0	0.0	0.0
Amortization	(36.5)	(37.7)	(39.8)	(41.0)
Other	0.3	(2.4)	(1.7)	0.1
Balance at end of period	864.3	900.5	1,017.6	1,059.1
Total
Amortization	(36.5)	(37.7)	(39.8)	(41.0)
Other intangibles
Finite-lived Intangible Assets [Roll Forward]
Balance at beginning of period	140.2	144.7	154.9	157.9
Additions at cost	0.3	0.1	0.1	0.1
Amortization	(4.1)	(4.1)	(4.2)	(4.2)
Other	0.0	(0.5)	1.7	1.1
Balance at end of period	136.4	140.2	152.5	154.9
Total
Amortization	$ (4.1)	$ (4.1)	$ (4.2)	$ (4.2)