Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Net income	$ 61.3	$ 54.0
Other comprehensive income (loss):
Defined benefit pension and other postretirement plans, net of income taxes	10.1	13.2
Currency translation adjustments	6.2	1.8
Gain (loss) from hedging activities, net of income taxes	(0.1)	0.7
Total other comprehensive income attributable to W. R. Grace & Co. shareholders	16.2	15.7
Total other comprehensive income attributable to noncontrolling interests	0.1
Total other comprehensive income	16.3	15.7
Comprehensive income	$ 77.6	$ 69.7