Revenue from Contracts with Clients (Client Receivables) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Total Client Receivables	$ 937.9	$ 1,052.1
Trust Fees Receivable, net
Disaggregation of Revenue [Line Items]
Total Client Receivables	882.5	925.2
Contract with customer, asset, allowance for credit loss	13.5	10.9
Other
Disaggregation of Revenue [Line Items]
Total Client Receivables	$ 55.4	$ 126.9