Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Tax Contingency [Line Items]
Effective income tax rate reconciliation, percent	30.70%	17.20%	33.70%	5.40%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%	21.00%
Income tax expense (benefit)	$ 98.5	$ 8.8	$ 97.1	$ 18.9
Continuing Operations | BAM
Income Tax Contingency [Line Items]
Income tax expense (benefit)		$ 3.6		$ 6.6