Equity - Rollforward of Accumlated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Beginning balance, value	$ 134.6	$ 517.4	$ 416.6
Other comprehensive income (loss) before reclassifications	7.6	(2.5)	(9.2)
Ending balance, value	277.9	134.6	517.4
Accumulated other comprehensive income (loss)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Beginning balance, value	(19.0)	(16.5)	(7.3)
Other comprehensive income (loss) before reclassifications	7.5	(3.5)	(11.1)
Amounts reclassified from accumulated other comprehensive income (loss)	0.1	1.0	1.9
Reclassification of certain deferred tax effects	(0.3)
Ending balance, value	(11.7)	(19.0)	(16.5)
Foreign currency adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Beginning balance, value	(18.4)	(15.5)	(6.3)
Other comprehensive income (loss) before reclassifications	8.3	(2.9)	(9.2)
Ending balance, value	(10.1)	(18.4)	(15.5)
Derivative Instruments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Beginning balance, value	0.0	(1.0)	(1.0)
Other comprehensive income (loss) before reclassifications	(0.1)	0.0	(1.9)
Amounts reclassified from accumulated other comprehensive income (loss)	0.1	1.0	1.9
Ending balance, value	0.0	0.0	(1.0)
Pension and other postretirement benefits
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax
Beginning balance, value	(0.6)	0.0	0.0
Other comprehensive income (loss) before reclassifications	(0.7)	(0.6)
Ending balance, value	$ (1.6)	$ (0.6)	$ 0.0