Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Tax Contingency [Line Items]
Effective income tax rate reconciliation, percent	17.20%	(8.10%)	5.40%	(1.20%)
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%		21.00%	21.00%
Income tax expense (benefit)	$ 8.8	$ (3.6)	$ 18.9	$ (0.4)
Continuing Operations | BAM
Income Tax Contingency [Line Items]
Income tax expense (benefit)	$ (3.6)	$ (1.8)	$ (6.6)	$ (4.0)