Goodwill and Other Intangibles - Goodwill (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Goodwill [Roll Forward]
Beginning Balance	$ 706.2	$ 707.2
Goodwill Acquired		4.2
Foreign Exchange Rates	(14.9)	(5.2)
Ending Balance	691.3	706.2
ASSET SERVICING
Goodwill [Roll Forward]
Beginning Balance	625.7	626.7
Goodwill Acquired		4.2
Foreign Exchange Rates	(14.7)	(5.2)
Ending Balance	611.0	625.7
WEALTH MANAGEMENT
Goodwill [Roll Forward]
Beginning Balance	80.5	80.5
Goodwill Acquired		0.0
Foreign Exchange Rates	(0.2)	0.0
Ending Balance	$ 80.3	$ 80.5