Consolidated Balance Sheets (unaudited) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current Assets
Cash and cash equivalents	$ 1,319.8	$ 1,336.9
Restricted cash and cash equivalents	201.6	197.6
Trade accounts receivable, less allowance of $5.0 (2012—$5.2)	429.6	474.8
Accounts receivable—unconsolidated affiliate	13.8	15.6
Inventories	317.8	278.6
Deferred income taxes	52.6	58.3
Other current assets	94.4	78.4
Total Current Assets	2,429.6	2,440.2
Properties and equipment, net of accumulated depreciation and amortization of $1,783.7 (2012—$1,785.1)	762.5	770.5
Goodwill	194.3	196.7
Patents, licenses and other intangible assets, net	78.9	82.7
Deferred income taxes	927.2	956.3
Asbestos-related insurance	500.0	500.0
Overfunded defined benefit pension plans	36.5	33.8
Investment in unconsolidated affiliate	90.5	85.5
Other assets	29.9	24.5
Total Assets	5,049.4	5,090.2
Current Liabilities
Debt payable within one year	67.5	83.4
Debt payable—unconsolidated affiliate	4.5	3.6
Accounts payable	284.8	249.4
Accounts payable—unconsolidated affiliate	1.4	2.6
Other current liabilities	238.9	307.3
Total Current Liabilities	597.1	646.3
Debt payable after one year	11.7	13.4
Debt payable—unconsolidated affiliate	21.7	22.4
Deferred income taxes	26.9	27.1
Underfunded and unfunded defined benefit pension plans	309.1	400.6
Other liabilities	45.1	45.0
Total Liabilities Not Subject to Compromise	1,011.6	1,154.8
Liabilities Subject to Compromise-Note 2
Debt plus accrued interest	981.1	973.3
Income tax contingencies	90.4	87.6
Asbestos-related contingencies	2,065.0	2,065.0
Environmental contingencies	139.3	140.5
Postretirement benefits	185.1	188.1
Other liabilities and accrued interest	165.3	162.6
Total Liabilities Subject to Compromise	3,626.2	3,617.1
Total Liabilities	4,637.8	4,771.9
Commitments and Contingencies—Note 10
Equity
Common stock issued, par value $0.01; 300,000,000 shares authorized; outstanding: 75,871,645 (2012—75,565,409)	0.8	0.8
Paid-in capital	542.7	536.5
Retained earnings	448.1	395.2
Treasury stock, at cost: shares: 1,108,115 (2012—1,414,351)	(13.2)	(16.8)
Accumulated other comprehensive loss	(577.2)	(607.3)
Total W. R. Grace & Co. Shareholders' Equity	401.2	308.4
Noncontrolling interests	10.4	9.9
Total Equity	411.6	318.3
Total Liabilities and Equity	$ 5,049.4	$ 5,090.2