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Related Party Transactions (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Net expenses from transactions with related parties		$ 2.4	$ 3.4	$ 3.8
Due to related parties	$ 1.0	2.0	1.0
Due from related parties	9.0	4.0	9.0
Other income (loss)		21.0	38.0	29.0
Affiliated Entity
Related Party Transaction [Line Items]
Due to related parties	$ 1.0	$ 1.0	1.0
Executive Officer
Related Party Transaction [Line Items]
Shares cancelled (in shares)	385,777
Other income (loss)			12.0
Equity in Earnings of Investees
Related Party Transaction [Line Items]
Revenue from related parties			$ 0.5	$ 1.0
Wellington Management Company LLP
Related Party Transaction [Line Items]
Ownership percentage by noncontrolling owners	5.00%	5.00%	5.00%
BlackRock Financial Management Inc.
Related Party Transaction [Line Items]
Ownership percentage by noncontrolling owners	5.00%	5.00%	5.00%