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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Tax Contingency [Line Items]
Effective income tax rate reconciliation, percent	(8.10%)	(47.60%)	1.20%	(203.90%)
U.S. statutory rate (as a percent)			21.00%	35.00%
Income tax expense (benefit)	$ (3.6)	$ (4.0)	$ (0.4)	$ (5.3)
Continuing Operations | BAM
Income Tax Contingency [Line Items]
Income tax expense (benefit)	$ (1.8)	$ (2.1)	$ (4.0)	$ (6.9)

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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