Equity - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 13,388.4	$ 10,959.7	$ 10,686.1
Net current period other comprehensive income (loss)	11.2	(58.2)	192.9
Ending balance	14,799.4	13,388.4	10,959.7
Accumulated other comprehensive income (loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(164.9)	(106.7)	(299.0)
Other comprehensive income (loss) before reclassifications	11.1	87.0	134.1
Amounts reclassified from AOCI	0.1	(145.2)	58.2
Net current period other comprehensive income (loss)	11.2	(58.2)	192.3
Ending balance	(153.7)	(164.9)	(106.7)
Unrealized Gains (Losses) on Securities Available for Sale, Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(15.7)	(2.2)	1.4
Other comprehensive income (loss) before reclassifications	2.3	(23.5)	(6.6)
Amounts reclassified from AOCI	13.4	10.0	3.0
Net current period other comprehensive income (loss)	15.7	(13.5)	(3.6)
Ending balance	0.0	(15.7)	(2.2)
Unrealized Gains (Losses) on Cash Flow Hedges, Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	15.1	53.8	(179.0)
Other comprehensive income (loss) before reclassifications	(26.8)	137.3	178.2
Amounts reclassified from AOCI	(13.3)	(176.0)	54.6
Net current period other comprehensive income (loss)	(40.1)	(38.7)	232.8
Ending balance	(25.0)	15.1	53.8
Gains (Losses) on Net Investment Hedges, Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0.0	25.5	(8.5)
Other comprehensive income (loss) before reclassifications		12.6	33.4
Amounts reclassified from AOCI		(38.1)	0.6
Net current period other comprehensive income (loss)		(25.5)	34.0
Ending balance		0.0	25.5
Unrealized Gains (Losses) on Pension Benefit Obligation, Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(1.1)	(44.8)	(66.3)
Other comprehensive income (loss) before reclassifications	(1.5)	43.7	21.5
Amounts reclassified from AOCI	0.0	0.0	0.0
Net current period other comprehensive income (loss)	(1.5)	43.7	21.5
Ending balance	(2.6)	(1.1)	(44.8)
Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(163.2)	(139.0)	(46.6)
Other comprehensive income (loss) before reclassifications	37.1	(83.1)	(92.4)
Amounts reclassified from AOCI	0.0	58.9	0.0
Net current period other comprehensive income (loss)	37.1	(24.2)	(92.4)
Ending balance	$ (126.1)	$ (163.2)	$ (139.0)