Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Net income	$ 69.7	$ 75.5	$ 131.0	$ 129.5
Other comprehensive income (loss):
Defined benefit pension and other postretirement plans, net of income taxes	(37.4)	21.8	(27.3)	35.0
Currency translation adjustments	(15.6)	(0.5)	(9.4)	1.3
Gain (loss) from hedging activities, net of income taxes	1.6	(0.2)	1.5	0.5
Total other comprehensive income attributable to noncontrolling interests	0.2	0.4	0.3	0.4
Total other comprehensive income (loss)	(51.2)	21.5	(34.9)	37.2
Comprehensive income	18.5	97.0	96.1	166.7
Less: comprehensive (income) loss attributable to noncontrolling interests	(0.6)	(0.1)	(1.1)	0.1
Comprehensive income attributable to W. R. Grace & Co. shareholders	$ 17.9	$ 96.9	$ 95.0	$ 166.8

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