Other Comprehensive Loss - AOCI (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 372.4	$ 212.5
Total other comprehensive income (loss)	(1.0)	(6.1)
Ending balance	395.7	468.4
Defined Benefit Pension and Other Postretirement Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	2.2	3.0
Other comprehensive income (loss) before reclassifications	0.0	0.0
Amounts reclassified from accumulated other comprehensive income (loss)	(0.3)	(0.3)
Total other comprehensive income (loss)	(0.3)	(0.3)
Distribution of GCP		(0.2)
Ending balance	1.9	2.5
Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	67.6	(66.1)
Other comprehensive income (loss) before reclassifications	(1.4)	(5.4)
Amounts reclassified from accumulated other comprehensive income (loss)	0.0	0.0
Total other comprehensive income (loss)	(1.4)	(5.4)
Distribution of GCP		135.5
Ending balance	66.2	64.0
Gain (loss) from Hedging Activities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(3.4)	(3.7)
Other comprehensive income (loss) before reclassifications	0.0	(3.4)
Amounts reclassified from accumulated other comprehensive income (loss)	0.7	0.4
Total other comprehensive income (loss)	0.7	(3.0)
Distribution of GCP		0.0
Ending balance	(2.7)	(6.7)
AOCI Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	66.4	(66.8)
Other comprehensive income (loss) before reclassifications	(1.4)	(8.8)
Amounts reclassified from accumulated other comprehensive income (loss)	0.4	0.1
Total other comprehensive income (loss)	(1.0)	(8.7)
Distribution of GCP		135.3
Ending balance	$ 65.4	$ 59.8