Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax beginning balance	$ (164.9)	$ (106.7)
Balance, January 1, 2018	(172.0)	(115.2)
Other comprehensive income (loss), before reclassifications, net of tax	7.6	8.4
Amounts reclassified from accumulated other comprehensive income, net of tax	(14.7)	(16.9)
Other comprehensive income (loss), net of tax	(7.1)	(8.5)
Accumulated other comprehensive income (loss), net of tax ending balance	(172.0)	(115.2)
Other comprehensive income (loss), net of tax	(7.1)	(8.5)
Unrealized gains (losses) on securities available for sale
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax beginning balance	(15.7)	(2.2)
Balance, January 1, 2018	(10.0)	(11.9)
Other comprehensive income (loss), before reclassifications, net of tax	5.3	(10.2)
Amounts reclassified from accumulated other comprehensive income, net of tax	0.4	0.5
Other comprehensive income (loss), net of tax	5.7	(9.7)
Accumulated other comprehensive income (loss), net of tax ending balance	(10.0)	(11.9)
Unrealized gains (losses) on cash flow hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax beginning balance	15.1	53.8
Balance, January 1, 2018	(20.3)	69.7
Other comprehensive income (loss), before reclassifications, net of tax	(20.3)	34.4
Amounts reclassified from accumulated other comprehensive income, net of tax	(15.1)	(18.5)
Other comprehensive income (loss), net of tax	(35.4)	15.9
Accumulated other comprehensive income (loss), net of tax ending balance	(20.3)	69.7
Gains (losses) on net investment hedge
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax beginning balance		25.5
Balance, January 1, 2018		31.7
Other comprehensive income (loss), before reclassifications, net of tax		5.1
Amounts reclassified from accumulated other comprehensive income, net of tax		1.1
Other comprehensive income (loss), net of tax		6.2
Accumulated other comprehensive income (loss), net of tax ending balance		31.7
Unfunded status of postretirement benefit plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax beginning balance	(1.1)	(44.8)
Balance, January 1, 2018	(0.6)	(43.9)
Other comprehensive income (loss), before reclassifications, net of tax	0.5	0.9
Amounts reclassified from accumulated other comprehensive income, net of tax	0.0	0.0
Other comprehensive income (loss), net of tax	0.5	0.9
Accumulated other comprehensive income (loss), net of tax ending balance	(0.6)	(43.9)
Currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), net of tax beginning balance	(163.2)	(139.0)
Balance, January 1, 2018	(141.1)	(160.8)
Other comprehensive income (loss), before reclassifications, net of tax	22.1	(21.8)
Amounts reclassified from accumulated other comprehensive income, net of tax	0.0	0.0
Other comprehensive income (loss), net of tax	22.1	(21.8)
Accumulated other comprehensive income (loss), net of tax ending balance	$ (141.1)	$ (160.8)