Significant Accounting Policies and Practices (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($) voting_interest_model_entity variable_interest_entity partnership	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Significant Accounting Policies and Practices
Restricted cash and cash equivalents	$ 0.3		$ 0.5
Number of ownership interest entities | partnership	30
Equity earnings in related investments	$ 0.6	$ 0.7
Deferred tax assets increased	41.6
Deferred tax assets	$ 52.2		$ 10.6
Primary Beneficiary
Significant Accounting Policies and Practices
Number of ownership interest entities | variable_interest_entity	25
Not Primary Beneficiary
Significant Accounting Policies and Practices
Number of ownership interest entities | voting_interest_model_entity	5