Reconciliation of Segment Operating Loss to Consolidated Loss Before Income Taxes (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating profit (loss)	$ (27.6)	$ (30.0)
Interest expense	(4.4)	(2.6)
Other income (expense), net	(1.2)	4.9
Cost reduction charges	(26.9)	0.0	$ (118.5)
Total loss before income taxes	(33.2)	(27.7)
Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating profit (loss)	18.0	(3.9)
Corporate and eliminations
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating profit (loss)	$ (18.7)	$ (26.1)