Consolidated Statements of Equity (unaudited) - USD ($) $ in Millions	Total	Common Stock and Paid-in Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests
Beginning balance at Dec. 31, 2015	$ 212.5	$ 496.7	$ 436.3	$ (658.4)	$ (66.8)	$ 4.7
Increase (Decrease) in Stockholders' Equity
Net income	0.3		0.5			(0.2)
Repurchase of common stock	(15.0)			(15.0)
Stock based compensation	3.6	3.6
Exercise of stock options	13.8	(4.6)		18.4
Tax benefit related to stock plans	(70.4)		(70.4)
Other comprehensive (loss) income	(6.1)				(8.7)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	(2.6)
Distribution of GCP	188.9		57.3		135.3	(3.7)
Ending balance at Mar. 31, 2016	468.4	495.7	564.5	(655.0)	59.8	3.4
Beginning balance at Dec. 31, 2016	372.4	488.0	619.3	(804.9)	66.4	3.6
Increase (Decrease) in Stockholders' Equity
Net income	42.9		42.9			0.0
Repurchase of common stock	(10.0)			(10.0)
RSU stock payout	(2.2)	(2.2)
Stock based compensation	2.4	2.4
Exercise of stock options	5.6	(8.8)		14.4
Other comprehensive (loss) income	(1.0)				(1.0)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	0.0
Dividends declared	14.4		14.4
Ending balance at Mar. 31, 2017	$ 395.7	$ 479.4	$ 647.8	$ (800.5)	$ 65.4	$ 3.6