Subsequent Event - Chapter 11 Emergence (Details) (USD $)	1 Months Ended	12 Months Ended
	Feb. 28, 2014	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011	Feb. 03, 2014	Dec. 31, 2010
Subsequent Event [Line Items]
Trade accounts receivable, allowance		$ 6,000,000		$ 5,200,000
Other Liabilities, Current		292,000,000		307,300,000
Emergence-related claims and other costs paid by Grace							1,900,000,000
Chapter 11 Expenses Paid	1,360,000,000	15,000,000		15,500,000		20,600,000
Senior Secured Credit Facilities to Fund Emergence	900,000,000
Pro Forma Income Tax Effects US Federal and State Tax Rate							37.41%
Cash and Cash Equivalents, at Carrying Value		(964,800,000)		(1,336,900,000)		(1,048,300,000)		(1,015,700,000)
Restricted cash and cash equivalents		(395,400,000)		(197,600,000)
Accounts Receivable, Net, Current		469,500,000		474,800,000
Accounts Receivable, Related Parties, Current		12,300,000		15,600,000
Inventories		295,300,000		283,600,000
Deferred Tax Assets, Net of Valuation Allowance, Current		58,100,000		58,300,000
Other current assets		99,000,000		78,400,000
Total Current Assets		(2,294,400,000)		(2,445,200,000)
Properties and equipment, net		829,900,000		770,500,000
Goodwill		457,500,000		196,700,000
Intangible Assets, Net (Excluding Goodwill)		315,500,000		82,700,000
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent		845,900,000		953,200,000
Net operating loss carryforward		0
Asbestos-related insurance		500,000,000		500,000,000
Overfunded defined benefit pension plans		16,700,000		32,100,000
Equity Method Investments		96,200,000		85,500,000
Other Assets, Noncurrent		40,000,000		24,500,000
Cash (Including Restricted Cash) Transferred to the Asbestos PI and PD Trusts	512,000,000
Total Assets		5,396,100,000		5,090,400,000		4,495,600,000
Debt payable within one year		76,600,000	[1]	83,400,000	[1]
Notes Payable, Related Parties, Current		4,500,000		3,600,000
Accounts payable		249,500,000		249,400,000
Accounts Payable, Related Parties, Current		13,000,000		2,600,000
PI warrant liability		0
Total Current Liabilities		635,600,000		646,300,000
Debt payable after one year		5,300,000		13,400,000
Notes Payable, Related Parties, Noncurrent		24,300,000		22,400,000
Deferred payment obligations		0
Deferred income taxes		18,200,000		27,100,000
Income tax contingencies		0
Underfunded defined benefit pension plans		66,200,000
Unfunded pay-as-you-go defined benefit pension plans		233,400,000
Other Liabilities, Noncurrent		65,800,000		45,000,000
Total Liabilities Not Subject to Compromise		1,048,800,000		1,150,700,000
Liabilities Subject to Compromise, Debt and Accrued Interest		1,137,800,000		973,300,000
Liabilities Subject to Compromise, Income Tax Contingencies		76,600,000		87,600,000
Liabilities Subject to Compromise, Asbestos Obligations		2,092,400,000		2,065,000,000
Liabilities Subject to Compromise, Environmental Contingencies		134,500,000		140,500,000
Liabilities Subject to Compromise, Pension and Other Postretirement Obligations		176,300,000		190,900,000
Liabilities Subject to Compromise, Other Liabilities		158,500,000		162,600,000
Total Liabilities Subject to Compromise		3,776,100,000		3,619,900,000
Total Liabilities		4,824,900,000		4,770,600,000
Common Stock, Value, Outstanding		800,000		800,000
Paid-in capital		533,400,000		536,500,000
Retained Earnings (Accumulated Deficit)		15,800,000		(240,300,000)
Treasury Stock, Value		0		16,800,000
Accumulated Other Comprehensive Income (Loss), Net of Tax		10,600,000		29,700,000
Total W. R. Grace & Co. Shareholders' Equity		560,600,000		309,900,000
Noncontrolling interests in shareholders' equity		10,600,000		9,900,000
Total Equity		571,200,000		319,800,000		184,100,000		(55,700,000)
Total Liabilities and Equity		5,396,100,000		5,090,400,000
US Federal and State NOL Carryforwards Increase Due to Payment of Bankruptcy Claims	670,000,000
Tax Effected US Federal and State NOL Carryforwards Increase Due to Payment of Bankruptcy Claims	252,000,000
Tax Deductions Attributable to PI and ZAI Deferred Payments							1,580,000,000
Tax Deductions Attributable to Warrant Settlement							490,000,000
Properties and equipment, accumulated depreciation and amortization		1,876,800,000		1,785,100,000
Common stock issued, par value (in dollars per share)		$ 0.01		$ 0.01
Common stock issued, shares authorized		300,000,000		300,000,000
Common stock issued, shares outstanding		77,046,143		75,565,409		73,886,050
Treasury Stock, Shares		0		1,414,351
Pro Forma [Member]
Subsequent Event [Line Items]
Other Liabilities, Current		338,000,000
Cash and Cash Equivalents, at Carrying Value		(350,800,000)
Restricted cash and cash equivalents		0
Accounts Receivable, Net, Current		469,500,000
Accounts Receivable, Related Parties, Current		12,300,000
Inventories		295,300,000
Deferred Tax Assets, Net of Valuation Allowance, Current		58,100,000
Other current assets		99,000,000
Total Current Assets		(1,285,000,000)
Properties and equipment, net		829,900,000
Goodwill		457,500,000
Intangible Assets, Net (Excluding Goodwill)		315,500,000
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent		600,800,000
Net operating loss carryforward		252,200,000
Asbestos-related insurance		0
Overfunded defined benefit pension plans		16,700,000
Equity Method Investments		96,200,000
Other Assets, Noncurrent		67,000,000
Total Assets		3,920,800,000
Debt payable within one year		85,600,000
Notes Payable, Related Parties, Current		4,500,000
Accounts payable		249,500,000
Accounts Payable, Related Parties, Current		13,000,000
PI warrant liability		490,000,000
Total Current Liabilities		1,180,600,000
Debt payable after one year		896,300,000
Notes Payable, Related Parties, Noncurrent		24,300,000
Deferred payment obligations		594,500,000
Deferred income taxes		18,200,000
Income tax contingencies		76,600,000
Underfunded defined benefit pension plans		66,200,000
Unfunded pay-as-you-go defined benefit pension plans		329,300,000
Other Liabilities, Noncurrent		171,000,000
Total Liabilities Not Subject to Compromise		3,357,000,000
Liabilities Subject to Compromise, Debt and Accrued Interest		0
Liabilities Subject to Compromise, Income Tax Contingencies		0
Liabilities Subject to Compromise, Asbestos Obligations		0
Liabilities Subject to Compromise, Environmental Contingencies		0
Liabilities Subject to Compromise, Pension and Other Postretirement Obligations		0
Liabilities Subject to Compromise, Other Liabilities		0
Total Liabilities Subject to Compromise		0
Total Liabilities		3,357,000,000
Common Stock, Value, Outstanding		800,000
Paid-in capital		533,400,000
Retained Earnings (Accumulated Deficit)		8,400,000
Treasury Stock, Value		0
Accumulated Other Comprehensive Income (Loss), Net of Tax		10,600,000
Total W. R. Grace & Co. Shareholders' Equity		553,200,000
Noncontrolling interests in shareholders' equity		10,600,000
Total Equity		563,800,000
Total Liabilities and Equity		3,920,800,000
Payment of Remaining Pre-Petition Liabilities and Adjustment for Additional Expenses [Member]
Subsequent Event [Line Items]
Other Liabilities, Current		7,200,000
Cash and Cash Equivalents, at Carrying Value		1,370,600,000
Restricted cash and cash equivalents		0
Accounts Receivable, Net, Current		0
Accounts Receivable, Related Parties, Current		0
Inventories		0
Deferred Tax Assets, Net of Valuation Allowance, Current		0
Other current assets		0
Total Current Assets		1,370,600,000
Properties and equipment, net		0
Goodwill		0
Intangible Assets, Net (Excluding Goodwill)		0
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent		(134,100,000)
Net operating loss carryforward		141,200,000
Asbestos-related insurance		0
Overfunded defined benefit pension plans		0
Equity Method Investments		0
Other Assets, Noncurrent		0
Other emergence costs		12,000,000
Total Assets		(1,363,500,000)
Debt payable within one year		0
Notes Payable, Related Parties, Current		0
Accounts payable		0
Accounts Payable, Related Parties, Current		0
PI warrant liability		0
Total Current Liabilities		7,200,000
Debt payable after one year		0
Notes Payable, Related Parties, Noncurrent		0
Deferred payment obligations		0
Deferred income taxes		0
Income tax contingencies		0
Underfunded defined benefit pension plans		0
Unfunded pay-as-you-go defined benefit pension plans		0
Other Liabilities, Noncurrent		0
Total Liabilities Not Subject to Compromise		7,200,000
Liabilities Subject to Compromise, Debt and Accrued Interest		(1,135,700,000)
Liabilities Subject to Compromise, Income Tax Contingencies		0
Liabilities Subject to Compromise, Asbestos Obligations		0
Liabilities Subject to Compromise, Environmental Contingencies		(77,500,000)
Liabilities Subject to Compromise, Pension and Other Postretirement Obligations		(27,700,000)
Liabilities Subject to Compromise, Other Liabilities		(122,400,000)
Total Liabilities Subject to Compromise		(1,363,300,000)
Total Liabilities		(1,356,100,000)
Common Stock, Value, Outstanding		0
Paid-in capital		0
Retained Earnings (Accumulated Deficit)		(7,400,000)
Treasury Stock, Value		0
Accumulated Other Comprehensive Income (Loss), Net of Tax		0
Total W. R. Grace & Co. Shareholders' Equity		(7,400,000)
Noncontrolling interests in shareholders' equity		0
Total Equity		(7,400,000)
Total Liabilities and Equity		(1,363,500,000)
Consideration to the Asbestos Trusts [Member]
Subsequent Event [Line Items]
Other Liabilities, Current		0
Cash and Cash Equivalents, at Carrying Value		(269,600,000)
Restricted cash and cash equivalents		(242,200,000)
Accounts Receivable, Net, Current		0
Accounts Receivable, Related Parties, Current		0
Inventories		0
Deferred Tax Assets, Net of Valuation Allowance, Current		0
Other current assets		0
Total Current Assets		(511,800,000)
Properties and equipment, net		0
Goodwill		0
Intangible Assets, Net (Excluding Goodwill)		0
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent		(111,000,000)
Net operating loss carryforward		111,000,000
Asbestos-related insurance		(500,000,000)
Overfunded defined benefit pension plans		0
Equity Method Investments		0
Other Assets, Noncurrent		0
Total Assets		(1,011,800,000)
Debt payable within one year		0
Notes Payable, Related Parties, Current		0
Accounts payable		0
Accounts Payable, Related Parties, Current		0
PI warrant liability		490,000,000
Total Current Liabilities		490,000,000
Debt payable after one year		0
Notes Payable, Related Parties, Noncurrent		0
Deferred payment obligations		594,500,000
Deferred income taxes		0
Income tax contingencies		0
Underfunded defined benefit pension plans		0
Unfunded pay-as-you-go defined benefit pension plans		0
Other Liabilities, Noncurrent		0
Total Liabilities Not Subject to Compromise		1,084,500,000
Liabilities Subject to Compromise, Debt and Accrued Interest		0
Liabilities Subject to Compromise, Income Tax Contingencies		0
Liabilities Subject to Compromise, Asbestos Obligations		(2,084,100,000)
Liabilities Subject to Compromise, Environmental Contingencies		0
Liabilities Subject to Compromise, Pension and Other Postretirement Obligations		0
Liabilities Subject to Compromise, Other Liabilities		(12,200,000)
Total Liabilities Subject to Compromise		(2,096,300,000)
Total Liabilities		(1,011,800,000)
Common Stock, Value, Outstanding		0
Paid-in capital		0
Retained Earnings (Accumulated Deficit)		0
Treasury Stock, Value		0
Accumulated Other Comprehensive Income (Loss), Net of Tax		0
Total W. R. Grace & Co. Shareholders' Equity		0
Noncontrolling interests in shareholders' equity		0
Total Equity		0
Total Liabilities and Equity		(1,011,800,000)
Borrowings [Member]
Subsequent Event [Line Items]
Other Liabilities, Current		0
Cash and Cash Equivalents, at Carrying Value		(873,000,000)
Restricted cash and cash equivalents		0
Accounts Receivable, Net, Current		0
Accounts Receivable, Related Parties, Current		0
Inventories		0
Deferred Tax Assets, Net of Valuation Allowance, Current		0
Other current assets		0
Total Current Assets		(873,000,000)
Properties and equipment, net		0
Goodwill		0
Intangible Assets, Net (Excluding Goodwill)		0
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent		0
Net operating loss carryforward		0
Asbestos-related insurance		0
Overfunded defined benefit pension plans		0
Equity Method Investments		0
Other Assets, Noncurrent		27,000,000
Total Assets		900,000,000
Debt payable within one year		9,000,000
Notes Payable, Related Parties, Current		0
Accounts payable		0
Accounts Payable, Related Parties, Current		0
PI warrant liability		0
Total Current Liabilities		9,000,000
Debt payable after one year		891,000,000
Notes Payable, Related Parties, Noncurrent		0
Deferred payment obligations		0
Deferred income taxes		0
Income tax contingencies		0
Underfunded defined benefit pension plans		0
Unfunded pay-as-you-go defined benefit pension plans		0
Other Liabilities, Noncurrent		0
Total Liabilities Not Subject to Compromise		900,000,000
Liabilities Subject to Compromise, Debt and Accrued Interest		0
Liabilities Subject to Compromise, Income Tax Contingencies		0
Liabilities Subject to Compromise, Asbestos Obligations		0
Liabilities Subject to Compromise, Environmental Contingencies		0
Liabilities Subject to Compromise, Pension and Other Postretirement Obligations		0
Liabilities Subject to Compromise, Other Liabilities		0
Total Liabilities Subject to Compromise		0
Total Liabilities		900,000,000
Common Stock, Value, Outstanding		0
Paid-in capital		0
Retained Earnings (Accumulated Deficit)		0
Treasury Stock, Value		0
Accumulated Other Comprehensive Income (Loss), Net of Tax		0
Total W. R. Grace & Co. Shareholders' Equity		0
Noncontrolling interests in shareholders' equity		0
Total Equity		0
Total Liabilities and Equity		900,000,000
Reclassifications at Emergence [Member]
Subsequent Event [Line Items]
Other Liabilities, Current		38,800,000
Cash and Cash Equivalents, at Carrying Value		(153,200,000)
Restricted cash and cash equivalents		153,200,000
Accounts Receivable, Net, Current		0
Accounts Receivable, Related Parties, Current		0
Inventories		0
Deferred Tax Assets, Net of Valuation Allowance, Current		0
Other current assets		0
Total Current Assets		0
Properties and equipment, net		0
Goodwill		0
Intangible Assets, Net (Excluding Goodwill)		0
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent		0
Net operating loss carryforward		0
Asbestos-related insurance		0
Overfunded defined benefit pension plans		0
Equity Method Investments		0
Other Assets, Noncurrent		0
Total Assets		0
Debt payable within one year		0
Notes Payable, Related Parties, Current		0
Accounts payable		0
Accounts Payable, Related Parties, Current		0
PI warrant liability		0
Total Current Liabilities		38,800,000
Debt payable after one year		0
Notes Payable, Related Parties, Noncurrent		0
Deferred payment obligations		0
Deferred income taxes		0
Income tax contingencies		76,600,000
Underfunded defined benefit pension plans		0
Unfunded pay-as-you-go defined benefit pension plans		95,900,000
Other Liabilities, Noncurrent		105,200,000
Total Liabilities Not Subject to Compromise		316,500,000
Liabilities Subject to Compromise, Debt and Accrued Interest		(2,100,000)
Liabilities Subject to Compromise, Income Tax Contingencies		(76,600,000)
Liabilities Subject to Compromise, Asbestos Obligations		(8,300,000)
Liabilities Subject to Compromise, Environmental Contingencies		(57,000,000)
Liabilities Subject to Compromise, Pension and Other Postretirement Obligations		(148,600,000)
Liabilities Subject to Compromise, Other Liabilities		(23,900,000)
Total Liabilities Subject to Compromise		(316,500,000)
Total Liabilities		0
Common Stock, Value, Outstanding		0
Paid-in capital		0
Retained Earnings (Accumulated Deficit)		0
Treasury Stock, Value		0
Accumulated Other Comprehensive Income (Loss), Net of Tax		0
Total W. R. Grace & Co. Shareholders' Equity		0
Noncontrolling interests in shareholders' equity		0
Total Equity		0
Total Liabilities and Equity		0
Term Loan B (USD) [Member]
Subsequent Event [Line Items]
Senior Secured Credit Facilities to Fund Emergence	700,000,000
Term Loan B (EUR) [Member]
Subsequent Event [Line Items]
Senior Secured Credit Facilities to Fund Emergence	$ 150,000,000

[1] Represents borrowings under various lines of credit and other borrowings, primarily by non-U.S. subsidiaries. At December 31, 2013, the fair value of Grace's debt payable within one year not subject to compromise approximated the recorded value of $76.6 million.