W.R. Grace & Co. (GRA) 10-Q 28 Jul 17 2017 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2017	Jul. 25, 2017
Document and Entity Information
Entity Registrant Name	W R GRACE & CO
Entity Central Index Key	1,045,309
Document Type	10-Q
Document Period End Date	Jun. 30, 2017
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		68,226,961
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q2

Consolidated Statements of Oper

Consolidated Statements of Operations (unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Net sales	$ 429.5	$ 390.5	$ 827.5	$ 753.3
Cost of goods sold	260.2	217.3	505	427.4
Gross profit	169.3	173.2	322.5	325.9
Selling, general and administrative expenses	70.3	66.4	136.8	134.4
Research and development expenses	12.9	12.4	26.1	24.1
Provision for environmental remediation, net	13.2	5.3	13.2	7.5
Equity in earnings of unconsolidated affiliate	(6.1)	(2.6)	(13.1)	(9.5)
Restructuring and repositioning expenses	5.4	9.4	7.7	23
Interest expense and related financing costs	20.1	19.8	39.6	41.8
Other (income) expense, net	(9.6)	3.1	(11.8)	13.8
Total costs and expenses	106.2	113.8	198.5	235.1
Income (loss) from continuing operations before income taxes	63.1	59.4	124	90.8
(Provision for) benefit from income taxes	(19.6)	(21.5)	(37.6)	(42.7)
Income (loss) from continuing operations	43.5	37.9	86.4	48.1
Income (loss) from discontinued operations, net of income taxes	0	0.6	0	(9.3)
Net income (loss)	43.5	38.5	86.4	38.8
Less: Net (income) loss attributable to noncontrolling interests	0.4	0.2	0.4	0.4
Net income (loss) attributable to W. R. Grace & Co. shareholders	43.9	38.7	86.8	39.2
Amounts Attributable to W. R. Grace & Co. Shareholders:
Income (loss) from continuing operations attributable to W. R. Grace & Co. shareholders	$ 43.9	$ 38.1	$ 86.8	$ 48.5
Basic earnings per share:
Income (loss) from continuing operations	$ 0.64	$ 0.54	$ 1.27	$ 0.69
Income (loss) from discontinued operations, net of income taxes	0	0.01	0	(0.13)
Net income (loss)	$ 0.64	$ 0.55	$ 1.27	$ 0.56
Weighted average number of basic shares	68.3	70.5	68.3	70.5
Diluted earnings per share:
Income (loss) from continuing operations	$ 0.64	$ 0.54	$ 1.27	$ 0.68
Income (loss) from discontinued operations, net of income taxes	0	0.01	0	(0.13)
Net income (loss)	$ 0.64	$ 0.55	$ 1.27	$ 0.55
Weighted average number of diluted shares	68.4	70.9	68.5	71
Dividends per common share	$ 0.21	$ 0.17	$ 0.42	$ 0.17

Consolidated Statements of Comp

Consolidated Statements of Comprehensive (Loss) Income (unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 43.5	$ 38.5	$ 86.4	$ 38.8
Other comprehensive income (loss):
Defined benefit pension and other postretirement plans, net of income taxes	(0.4)	(0.4)	(0.7)	(0.7)
Currency translation adjustments	(8.3)	1.3	(9.7)	(4.1)
Gain (loss) from hedging activities, net of income taxes	(0.2)	(0.3)	0.5	(3.3)
Total other comprehensive income (loss) attributable to noncontrolling interests		0	0	2.6
Total other comprehensive income (loss)	(8.9)	0.6	(9.9)	(5.5)
Comprehensive income (loss)	34.6	39.1	76.5	33.3
Less: comprehensive (income) loss attributable to noncontrolling interests	0.4	0.2	0.4	(2.2)
Comprehensive income (loss) attributable to W. R. Grace & Co. shareholders	$ 35	$ 39.3	$ 76.9	$ 31.1

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Jun. 30, 2016
OPERATING ACTIVITIES
Net income (loss)	$ 43.5	$ 86.4	$ 38.8
(Loss) income from discontinued operations, net of income taxes	0	0	9.3
Income from continuing operations	43.5	86.4	48.1
Reconciliation to net cash provided by (used for) operating activities from continuing operations:
Depreciation and amortization		54.2	46.8
Equity in earnings of unconsolidated affiliate	(6.1)	(13.1)	(9.5)
Dividends received from unconsolidated affiliate		0	16.8
(Costs) benefit related to legacy product, environmental and other claims	14.9	17	11.1
Cash paid for legacy product, environmental and other claims		44.2	6
Provision for (benefit from) income taxes	19.6	37.6	42.7
Cash paid for income taxes		31.3	26.8
Income tax refunds received		29.7	2.3
Loss on early extinguishment of debt	0	0	11.1
Interest expense and related financing costs	20.1	39.6	41.8
Cash paid for interest		(34.3)	(40.6)
Defined benefit pension expense		8.2	5.3
Cash paid under defined benefit pension arrangements		(7.8)	(8)
Restructuring Charges	2	4.8	16.4
Cash paid for restructuring		(7.2)
Changes in assets and liabilities, excluding effect of currency translation and acquisitions:
Trade accounts receivable		4.3	37.2
Inventories		(3.9)	(7.7)
Accounts payable		7.4	7
All other items, net		(9.3)	(34.8)
Net cash provided by (used for) operating activities from continuing operations		140.5	136.8
INVESTING ACTIVITIES
Capital expenditures		(59.1)	(57.3)
Business acquired		0	245.1
Proceeds from sale of product lines		0.6	11.3
Other investing activities		(1.1)	(0.6)
Net cash provided by (used for) investing activities from continuing operations		(59.6)	(291.7)
FINANCING ACTIVITIES
Borrowings under credit arrangements		98.8	16
Repayments under credit arrangements		(61.5)	(609.4)
Cash paid for repurchases of common stock		30	35.1
Proceeds from exercise of stock options		12.2	9.2
Dividends paid		(28.7)	(12)
Distribution from GCP		0	750
Other financing activities		(4)	(2.7)
Net cash provided by (used for) financing activities from continuing operations		(13.2)	116
Effect of currency exchange rate changes on cash and cash equivalents		3.5	1.9
Increase (decrease) in cash and cash equivalents from continuing operations		71.2	(37)
Cash flows from discontinued operations
Net cash provided by (used for) operating activities		0	23.9
Net cash provided by (used for) investing activities		0	(9.5)
Net cash provided by (used for) financing activities		0	31.4
Effect of currency exchange rate changes on cash and cash equivalents		0	(1)
Increase (decrease) in cash and cash equivalents from discontinued operations		0	44.8
Net increase (decrease) in cash and cash equivalents		71.2	7.8
Less: cash and cash equivalents of discontinued operations	0	0
Cash and cash equivalents, beginning of period		90.6
Cash and cash equivalents, end of period	$ 161.8	161.8
Supplemental Cash Flow Information [Abstract]
Capital expenditures in accounts payable		17.8	19.7
Net share settled stock option exercises		1.2	10.1
Scenario, Previously Reported
Cash flows from discontinued operations
Cash and cash equivalents, beginning of period		$ 90.6	329.9
Cash and cash equivalents, end of period			$ 194.3

Consolidated Balance Sheets (un

Consolidated Balance Sheets (unaudited) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Current Assets
Cash and cash equivalents	$ 161.8	$ 90.6
Restricted cash and cash equivalents	10.8	10
Trade accounts receivable, less allowance of $2.4 (2016—$2.2)	265	273.9
Inventories	236.5	228
Other current assets	41.4	52.3
Total Current Assets	715.5	654.8
Properties and equipment, net of accumulated depreciation and amortization of $1,397.6 (2016—$1,327.5)	749.7	729.6
Goodwill	397.5	394.2
Technology and other intangible assets, net	261.9	269.1
Deferred income taxes	700.3	709.4
Investment in unconsolidated affiliate	131.9	117.6
Other assets	33.1	37.1
Total Assets	2,989.9	2,911.8
Current Liabilities
Debt payable within one year	86.5	76.5
Accounts payable	199.9	195.4
Other current liabilities	183.6	208.9
Total Current Liabilities	470	480.8
Debt payable after one year	1,516.5	1,507.6
Underfunded and unfunded defined benefit pension plans	444.2	424.3
Other liabilities	153.6	126.7
Total Liabilities	2,584.3	2,539.4
Equity
Common stock issued, par value $0.01; 300,000,000 shares authorized; outstanding: 68,226,070 (2016—68,309,431)	0.7	0.7
Paid-in capital	474	487.3
Retained earnings	677.3	619.3
Treasury stock, at cost: shares: 9,230,557 (2016—9,147,196)	(806.1)	(804.9)
Accumulated other comprehensive income (loss)	56.5	66.4
Total W. R. Grace & Co. Shareholders' Equity	402.4	368.8
Noncontrolling interests	3.2	3.6
Total Equity	405.6	372.4
Total Liabilities and Equity	$ 2,989.9	$ 2,911.8

Consolidated Balance Sheets (u6

Consolidated Balance Sheets (unaudited) (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Trade accounts receivable, less allowance	$ 2.4	$ 2.2
Properties and equipment, net of accumulated depreciation and amortization	$ 1,397.6	$ 1,327.5
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	68,226,070	68,309,431
Treasury stock, at cost (shares)	9,230,557	9,147,196

Consolidated Statements of Equi

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	38.8		39.2			(0.4)
Repurchase of common stock	(35.1)			(35.1)
Stock based compensation	6.5	6.5
Exercise of stock options	19.3	(10.5)		29.8
Tax benefit related to stock plans	72.3		72.3
Shares issued	0.7	0.7	0	0	0	0
Other comprehensive (loss) income	(5.5)				(8.1)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	(2.6)
Cash dividends declared	(12)		(12)
Distribution of GCP	191.5		59.9		135.3	(3.7)
Ending balance at Jun. 30, 2016	489	493.4	595.7	(663.7)	60.4	3.2
Beginning balance at Dec. 31, 2016	372.4	488	619.3	(804.9)	66.4	3.6
Increase (Decrease) in Stockholders' Equity
Net income	86.4		86.8			(0.4)
Repurchase of common stock	(30)			(30)
Payments to taxing authorities in consideration of employee tax obligations relative to stock-based compensation arrangements	(2.4)	(2.4)
Stock based compensation	5.4	5.4
Exercise of stock options	11.8	(17)		28.8
Shares issued	0.7	0.7	0	0	0	0
Other comprehensive (loss) income	(9.9)				(9.9)
Dividends declared	28.8		28.8
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	0
Ending balance at Jun. 30, 2017	$ 405.6	$ 474.7	$ 677.3	$ (806.1)	$ 56.5	$ 3.2

Basis of Presentation and Summa

Basis of Presentation and Summary of Significant Accounting and Financial Reporting Policies	6 Months Ended
	Jun. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Summary of Significant Accounting and Financial Reporting Policies	W. R. Grace & Co., through its subsidiaries, is engaged in specialty chemicals and specialty materials businesses on a global basis through two reportable segments: Grace Catalysts Technologies, which includes catalysts and related products and technologies used in refining, petrochemical and other chemical manufacturing applications; and Grace Materials Technologies, which includes specialty materials, including silica-based and silica-alumina-based materials, used in coatings, consumer, industrial, and pharmaceutical applications. W. R. Grace & Co. conducts all of its business through a single wholly owned subsidiary, W. R. Grace & Co.–Conn. ("Grace–Conn."). Grace–Conn. owns all of the assets, properties and rights of W. R. Grace & Co. on a consolidated basis, either directly or through subsidiaries. As used in these notes, the term "Company" refers to W. R. Grace & Co. The term "Grace" refers to the Company and/or one or more of its subsidiaries and, in certain cases, their respective predecessors. Separation Transaction On January 27, 2016, Grace entered into a separation agreement with GCP Applied Technologies Inc., then a wholly-owned subsidiary of Grace ("GCP"), pursuant to which Grace agreed to transfer its Grace Construction Products operating segment and the packaging technologies business of its Grace Materials Technologies operating segment to GCP (the "Separation"). Grace and GCP completed the Separation on February 3, 2016 (the "Distribution Date"), by means of a pro rata distribution to the Company's stockholders of all of the outstanding shares of GCP common stock (the "Distribution"), with one share of GCP common stock distributed for each share of Company common stock held as of the close of business on January 27, 2016. As a result of the Distribution, GCP became an independent public company. GCP’s historical financial results through the Distribution Date are reflected in Grace’s Consolidated Financial Statements as discontinued operations. Basis of Presentation The interim Consolidated Financial Statements presented herein are unaudited and should be read in conjunction with the Consolidated Financial Statements presented in the Company's 2016 Annual Report on Form 10-K. Such interim Consolidated Financial Statements reflect all adjustments that, in the opinion of management, are necessary for a fair statement of the results of the interim periods presented; all such adjustments are of a normal recurring nature except for the impacts of adopting new accounting standards as discussed below. All significant intercompany accounts and transactions have been eliminated. The results of operations for the six-month interim period ended June 30, 2017 , are not necessarily indicative of the results of operations to be attained for the year ending December 31, 2017 . Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles ("U.S. GAAP") requires management to make estimates and assumptions that affect the reported amount of assets and liabilities and disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements, and the reported amounts of revenues and expenses for the periods presented. Actual amounts could differ from those estimates, and the differences could be material. Changes in estimates are recorded in the period identified. Grace's accounting measurements that are most affected by management's estimates of future events are: • Realization values of net deferred tax assets, which depend on projections of future taxable income (see Note 5); • Pension and postretirement liabilities, which depend on assumptions regarding participant life spans, future inflation, discount rates and total returns on invested funds (see Note 6); • Carrying values of goodwill and other intangible assets, which depend on assumptions of future earnings and cash flows; and • Contingent liabilities, which depend on an assessment of the probability of loss and an estimate of ultimate obligation, such as litigation (see Note 8), income taxes (see Note 5), and environmental remediation (see Note 8). Reclassifications Certain amounts in prior years' Consolidated Financial Statements have been reclassified to conform to the current year presentation. Such reclassifications have not materially affected previously reported amounts in the Consolidated Financial Statements. Recently Issued Accounting Standards In May 2014, the FASB issued ASU 2014-09 "Revenue from Contracts with Customers." This update is intended to remove inconsistencies and weaknesses in revenue requirements; provide a more robust framework for addressing revenue issues; improve comparability of revenue recognition practices across entities, industries, jurisdictions and capital markets; provide more useful information to users of financial statements through improved disclosure requirements; and simplify the preparation of financial statements by reducing the number of requirements to which an entity must refer. The new requirements are effective for fiscal years beginning after December 15, 2017, and for interim periods within those fiscal years, with early adoption permitted for fiscal years beginning after December 15, 2016. The standard allows for two methods of adoption: (a) full retrospective adoption, meaning the standard is applied to all periods presented, or (b) modified retrospective adoption, meaning the cumulative effect of applying the new standard is recognized as an adjustment to the opening retained earnings balance. Grace will adopt the standard in the 2018 first quarter. Grace has begun its preliminary assessment and is identifying specific areas of impact on the Consolidated Financial Statements. At this time, Grace cannot reasonably estimate the effect of adoption. Grace has tentatively decided to adopt this standard under the modified retrospective approach and is still evaluating the effect on its financial statements and disclosures. In February 2016, the FASB issued ASU 2016-02 "Leases (Topic 842)." This update is intended to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. The core principle of Topic 842 is that a lessee should recognize the assets and liabilities that arise from leases. A lessee should recognize in the statement of financial position a liability to make lease payments (the lease liability) and a right-of-use asset representing its right to use the underlying asset for the lease term, including optional payments where they are reasonably certain to occur. The amendments in this update are effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, with early adoption permitted. Currently, as a lessee, Grace is a party to a number of leases which, under existing guidance, are classified as operating leases and not recorded on the balance sheet but are expensed as incurred. Under the new standard, many of these leases will be recorded on the Consolidated Balance Sheets. Grace will adopt the standard in 2019 and at this time cannot reasonably estimate the effect of adoption. In November 2016, the FASB issued ASU 2016-18 "Statement of Cash Flows (Topic 230): Restricted Cash," which requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash or restricted cash equivalents. Therefore, amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. The new requirements are effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years, with early adoption permitted. Grace is currently evaluating the timing of adoption and does not expect the update to have a material effect on the Consolidated Financial Statements. As of June 30, 2017 , and December 31, 2016 , restricted cash included in the Consolidated Balance Sheets was $10.8 million and $10.0 million , respectively. In January 2017, the FASB issued ASU 2017-01 "Business Combinations (Topic 805)," which provides a screen to determine when an integrated set of assets and activities is not a business. The screen requires that when substantially all of the fair value of the gross assets acquired (or disposed of) is concentrated in a single identifiable asset or a group of similar identifiable assets, the set is not a business. This screen reduces the number of transactions that need to be further evaluated. If the screen is not met, the amendments in this update (1) require that to be considered a business, a set must include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create output and (2) remove the evaluation of whether a market participant could replace missing elements. The amendments in this update also narrow the definition of the term "output" so that the term is consistent with how outputs are described in Topic 606. Public business entities are required to apply the amendments in this update to annual periods beginning after December 15, 2017, including interim periods within those periods. Early application is permitted. Grace will evaluate the effect of the update at the time of any future acquisition or disposal. In January 2017, the FASB issued ASU 2017-04 "Intangibles—Goodwill and Other (Topic 350)." This update modifies the concept of impairment from the condition that exists when the carrying amount of goodwill exceeds its implied fair value to the condition that exists when the carrying amount of a reporting unit exceeds its fair value. An entity no longer will determine goodwill impairment by calculating the implied fair value of goodwill by assigning the fair value of a reporting unit to all of its assets and liabilities as if that reporting unit had been acquired in a business combination ("Step 2"). Because these amendments eliminate Step 2 from the goodwill impairment test, they should reduce the cost and complexity of evaluating goodwill for impairment. Public business entities are required to adopt the amendments in this update for annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. Grace is currently evaluating the timing of adoption and does not expect the update to have a material effect on the Consolidated Financial Statements. In March 2017, the FASB issued ASU 2017-07 "Compensation—Retirement Benefits (Topic 715)." This update requires that the service cost component of net benefit cost be presented with other compensation costs arising from services rendered. The remaining net benefit cost is either presented as a line item in the statement of operations outside of a subtotal for income from operations, if presented, or disclosed separately. Only the service cost component of net benefit expense can be capitalized. Public business entities are required to adopt the amendments in this update for fiscal years beginning after December 15, 2017. Grace is currently evaluating the update's effect on the Consolidated Financial Statements and will adopt the update in the 2018 first quarter. In May 2017, the FASB issued ASU 2017-09 "Compensation—Stock Compensation (Topic 718)." This update clarifies the existing definition of the term "modification," which is currently defined as "a change in any of the terms or conditions of a share-based payment award." The update requires entities to account for modifications of share-based payment awards unless the (1) fair value, (2) vesting conditions and (3) classification as an equity instrument or a liability instrument of the modified award are the same as of the original award before modification. Public business entities are required to adopt the amendments in this update for fiscal years and interim periods beginning after December 15, 2017, with early adoption permitted. Grace does not currently have any modifications of share-based awards and will adopt the update when it becomes effective. Recently Adopted Accounting Standards In July 2015, the FASB issued ASU 2015-11 "Simplifying the Measurement of Inventory." This update is part of the FASB's Simplification Initiative and is also intended to enhance convergence with the International Accounting Standards Board's ("IASB") measurement of inventory. The update requires that inventory be measured at the lower of cost or net realizable value for entities using FIFO (first-in, first-out) or average cost methods. The new requirements are effective for fiscal years beginning after December 15, 2016, and for interim periods within those fiscal years, with early adoption permitted. Grace adopted this update in the first quarter of 2017, and it did not have a material effect on the Consolidated Financial Statements. In August 2016, the FASB issued ASU 2016-15 "Classification of Certain Cash Receipts and Cash Payments." This update is intended to reduce diversity in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. It addresses eight specific issues. The amendments in this update are effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years, with early adoption permitted. Grace adopted this update in the 2017 second quarter, and it did not have a material effect on the Consolidated Financial Statements.

Inventories

Inventories	6 Months Ended
	Jun. 30, 2017
Inventory Disclosure [Abstract]
Inventories	Inventories are stated at the lower of cost or net realizable value, and cost is determined using FIFO. Inventories consisted of the following at June 30, 2017 , and December 31, 2016 : (In millions) June 30, December 31, Raw materials $ 55.3 $ 57.7 In process 36.0 33.4 Finished products 123.1 115.8 Other 22.1 21.1 $ 236.5 $ 228.0

Debt

Debt	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Debt	Components of Debt (In millions) June 30, December 31, 5.125% senior notes due 2021, net of unamortized debt issuance costs of $6.6 at June 30, 2017 (2016—$7.3) $ 693.4 $ 692.7 U.S. dollar term loan, net of unamortized debt issuance costs and discounts of $5.1 at June 30, 2017 (2016—$5.7) 403.3 402.7 5.625% senior notes due 2024, net of unamortized debt issuance costs of $3.7 at June 30, 2017 (2016—$4.0) 296.3 296.0 Euro term loan, net of unamortized debt issuance costs and discounts of $1.1 at June 30, 2017 (2016—$1.3) 89.9 82.5 Revolving credit facility 40.0 — Debt payable to unconsolidated affiliate 40.0 39.5 Deferred payment obligation — 30.0 Other borrowings(1) 40.1 40.7 Total debt 1,603.0 1,584.1 Less debt payable within one year 86.5 76.5 Debt payable after one year $ 1,516.5 $ 1,507.6 Weighted average interest rates on total debt 4.6 % 4.6 % ___________________________________________________________________________________________________________________ (1) Represents borrowings under various lines of credit and other borrowings, primarily by non-U.S. subsidiaries. See Note 4 for a discussion of the fair value of Grace's debt. The principal maturities of debt outstanding at June 30, 2017 , were as follows: (In millions) 2017 $ 82.4 2018 8.4 2019 7.8 2020 6.6 2021 1,191.7 Thereafter 306.1 Total debt $ 1,603.0 On February 3, 2017, Grace funded the PD trust with $30.0 million in respect of the deferred payment obligation relating to ZAI PD Claims. (See Note 8.) As of June 30, 2017 , the available credit under the $300 million revolving credit facility was reduced to $222.3 million by a $40.0 million outstanding draw and by outstanding letters of credit. During the 2016 first quarter, in connection with the Separation, GCP distributed $750 million to Grace. Grace used $600 million of those funds to repay $526.9 million of its U.S. dollar term loan and €67.3 million of its euro term loan. As a result, Grace recorded a loss on early extinguishment of debt of $11.1 million , which is included in "other (income) expense, net" in the Consolidated Statements of Operations.

Fair Value Measurements and Ris

Fair Value Measurements and Risk	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements and Risk	Certain of Grace's assets and liabilities are reported at fair value on a gross basis. ASC 820 "Fair Value Measurements and Disclosures" defines fair value as the value that would be received at the measurement date in the principal or "most advantageous" market. Grace uses principal market data, whenever available, to value assets and liabilities that are required to be reported at fair value. Grace has identified the following financial assets and liabilities that are subject to the fair value analysis required by ASC 820: Fair Value of Debt and Other Financial Instruments Debt payable is recorded at carrying value. Fair value is determined based on Level 2 inputs, including expected future cash flows (discounted at market interest rates), estimated current market prices and quotes from financial institutions. At June 30, 2017 , the carrying amounts and fair values of Grace's debt were as follows: June 30, 2017 December 31, 2016 (In millions) Carrying Amount Fair Value Carrying Amount Fair Value 5.125% senior notes due 2021(1) $ 693.4 $ 745.4 $ 692.7 $ 721.3 U.S. dollar term loan(2) 403.3 402.8 402.7 408.2 5.625% senior notes due 2024(1) 296.3 318.5 296.0 311.5 Euro term loan(2) 89.9 89.9 82.5 82.0 Other borrowings 120.1 120.1 110.2 110.2 Total debt $ 1,603.0 $ 1,676.7 $ 1,584.1 $ 1,633.2 ___________________________________________________________________________________________________________________ (1) Carrying amounts are net of unamortized debt issuance costs of $6.6 million and $3.7 million as of June 30, 2017 , and $7.3 million and $4.0 million as of December 31, 2016 , related to the 5.125% senior notes due 2021 and 5.625% senior notes due 2024, respectively. (2) Carrying amounts are net of unamortized debt issuance costs and discounts of $5.1 million and $1.1 million as of June 30, 2017 , and $5.7 million and $1.3 million as of December 31, 2016 , related to the U.S. dollar term loan and euro term loan, respectively. At June 30, 2017 , the recorded values of other financial instruments such as cash equivalents and trade receivables and payables approximated their fair values, based on the short-term maturities and floating rate characteristics of these instruments. Currency Derivatives Because Grace operates and/or sells to customers in over 60 countries and in 30 currencies, its results are exposed to fluctuations in currency exchange rates. Grace seeks to minimize exposure to these fluctuations by matching sales in volatile currencies with expenditures in the same currencies, but it is not always possible to do so. From time to time, Grace will use financial instruments such as currency forward contracts, options, swaps, or combinations thereof to reduce the risk of certain specific transactions. However, Grace does not have a policy of hedging all exposures, because management does not believe that such a level of hedging would be cost-effective. Forward contracts with maturities of not more than 12 months are used and designated as cash flow hedges of forecasted repayments of intercompany loans. The effective portion of gains and losses on these currency hedges is recorded in "accumulated other comprehensive income (loss)" and reclassified into "other (income) expense" when these derivatives mature. The valuation of Grace's currency exchange rate forward contracts and swaps is determined using both a market approach and an income approach. Inputs used to value currency exchange rate forward contracts consist of: (1) spot rates, which are quoted by various financial institutions; (2) forward points, which are primarily affected by changes in interest rates; and (3) discount rates used to present value future cash flows, which are based on the London Interbank Offered Rate (LIBOR) curve or overnight indexed swap rates. Debt and Interest Rate Swap Agreements Grace uses interest rate swaps designated as cash flow hedges to manage fluctuations in interest rates on variable rate debt. The effective portion of gains and losses on these interest rate cash flow hedges is recorded in "accumulated other comprehensive income (loss)" and reclassified into "interest expense and related financing costs" during the hedged interest period. In connection with its emergence financing, Grace entered into an interest rate swap beginning on February 3, 2015, and maturing on February 3, 2020, fixing the LIBOR component of the interest on $250 million of Grace's term debt at a rate of 2.393% . The valuation of this interest rate swap is determined using both a market approach and an income approach, using prevailing market interest rates and discount rates to present value future cash flows based on the forward LIBOR yield curves. The following tables present the fair value hierarchy for financial assets and liabilities measured at fair value on a recurring basis as of June 30, 2017 , and December 31, 2016 : Fair Value Measurements at June 30, 2017, Using (In millions) Total Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Currency derivatives $ 3.6 $ — $ 3.6 $ — Total Assets $ 3.6 $ — $ 3.6 $ — Liabilities Interest rate derivatives $ 5.1 $ — $ 5.1 $ — Currency derivatives 11.6 — 11.6 — Total Liabilities $ 16.7 $ — $ 16.7 $ — Fair Value Measurements at December 31, 2016, Using (In millions) Total Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Currency derivatives $ 8.8 $ — $ 8.8 $ — Total Assets $ 8.8 $ — $ 8.8 $ — Liabilities Interest rate derivatives $ 6.0 $ — $ 6.0 $ — Currency derivatives 0.9 — 0.9 — Total Liabilities $ 6.9 $ — $ 6.9 $ — The following tables present the location and fair values of derivative instruments included in the Consolidated Balance Sheets as of June 30, 2017 , and December 31, 2016 : June 30, 2017 Asset Derivatives Liability Derivatives Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as hedging instruments under ASC 815: Currency contracts Other current assets $ 3.0 Other current liabilities $ 0.4 Interest rate contracts Other current assets — Other current liabilities 1.9 Currency contracts Other assets — Other liabilities 10.5 Interest rate contracts Other assets — Other liabilities 3.2 Derivatives not designated as hedging instruments under ASC 815: Currency contracts Other current assets 0.6 Other current liabilities 0.7 Total derivatives $ 3.6 $ 16.7 December 31, 2016 Asset Derivatives Liability Derivatives Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as hedging instruments under ASC 815: Currency contracts Other current assets $ 4.0 Other current liabilities $ — Interest rate contracts Other current assets — Other current liabilities 2.8 Currency contracts Other assets 4.0 Other liabilities — Interest rate contracts Other assets — Other liabilities 3.2 Derivatives not designated as hedging instruments under ASC 815: Currency contracts Other current assets 0.8 Other current liabilities 0.9 Total derivatives $ 8.8 $ 6.9 The following tables present the location and amount of gains and losses on derivative instruments included in the Consolidated Statements of Operations or, when applicable, gains and losses initially recognized in other comprehensive income (loss) ("OCI") for the three and six months ended June 30, 2017 and 2016 : Three Months Ended June 30, 2017 Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from OCI into Income (Effective Portion) Derivatives in ASC 815 cash flow hedging relationships: Interest rate contracts $ (1.1 ) Interest expense $ (0.8 ) Currency contracts — Other expense (0.1 ) Total derivatives $ (1.1 ) $ (0.9 ) Six Months Ended June 30, 2017 Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from OCI into Income (Effective Portion) Derivatives in ASC 815 cash flow hedging relationships: Interest rate contracts $ (1.0 ) Interest expense $ (1.7 ) Currency contracts (0.1 ) Other expense (0.1 ) Total derivatives $ (1.1 ) $ (1.8 ) Three Months Ended June 30, 2016 Amount of Gain (Loss) Recognized in OCI on Derivatives Location of Gain (Loss) Reclassified from Accumulated OCI into Income Amount of Gain (Loss) Reclassified from OCI into Income Derivatives in ASC 815 cash flow hedging relationships: Interest rate contracts $ (1.9 ) Interest expense $ (1.1 ) Currency contracts 0.2 Other expense (0.1 ) Total derivatives $ (1.7 ) $ (1.2 ) Six Months Ended June 30, 2016 Amount of Gain (Loss) Recognized in OCI on Derivatives Location of Gain (Loss) Reclassified from Accumulated OCI into Income Amount of Gain (Loss) Reclassified from OCI into Income Derivatives in ASC 815 cash flow hedging relationships: Interest rate contracts $ (6.4 ) Interest expense $ (2.1 ) Currency contracts 0.1 Other expense 0.4 Total derivatives $ (6.3 ) $ (1.7 ) Net Investment Hedges Grace uses cross-currency swaps as derivative hedging instruments in certain net investment hedges of its non-U.S. subsidiaries. The effective portion of gains and losses attributable to these net investment hedges is recorded net of tax to "currency translation adjustments" within "accumulated other comprehensive income (loss)" to offset the change in the carrying value of the net investment being hedged. Recognition in earnings of amounts previously recorded to "currency translation adjustments" is limited to circumstances such as complete or substantially complete liquidation of the net investment in the hedged foreign operation. At June 30, 2017 , the notional amount of €170.0 million of Grace's cross-currency swaps was designated as a hedging instrument of its net investment in its European subsidiaries. Grace also uses foreign currency denominated debt and deferred intercompany royalties as non-derivative hedging instruments in certain net investment hedges. The effective portion of gains and losses attributable to these net investment hedges is recorded to "currency translation adjustments" within "accumulated other comprehensive income (loss)." Recognition in earnings of amounts previously recorded to "currency translation adjustments" is limited to circumstances such as complete or substantially complete liquidation of the net investment in the hedged foreign operation. At June 30, 2017 , €80.1 million of Grace's term loan principal was designated as a hedging instrument of its net investment in its European subsidiaries. At June 30, 2017 , €45.0 million of Grace's deferred intercompany royalties was designated as a hedging instrument of its net investment in its European subsidiaries. The following tables present the location and amount of gains and losses on derivative and non-derivative instruments designated as net investment hedges for the three and six months ended June 30, 2017 and 2016 . There were no reclassifications of the effective portion of net investment hedges out of OCI and into earnings for the periods presented in the tables below. Three Months Ended June 30, 2017 Amount of Gain (Loss) Recognized in OCI in Currency Translation Adjustments (Effective Portion) Derivatives in ASC 815 net investment hedging relationships: Cross-currency swap $ (6.1 ) Non-derivatives in ASC 815 net investment hedging relationships: Foreign currency denominated debt $ (4.9 ) Foreign currency denominated deferred intercompany royalties (2.9 ) $ (7.8 ) Six Months Ended June 30, 2017 Amount of Gain (Loss) Recognized in OCI in Currency Translation Adjustments (Effective Portion) Derivatives in ASC 815 net investment hedging relationships: Cross-currency swap $ (8.6 ) Non-derivatives in ASC 815 net investment hedging relationships: Foreign currency denominated debt $ (7.2 ) Foreign currency denominated deferred intercompany royalties (4.4 ) $ (11.6 ) Three Months Ended June 30, 2016 Amount of Gain (Loss) Recognized in OCI in Currency Translation Adjustments (Effective Portion) Derivatives in ASC 815 net investment hedging relationships: Cross-currency swap $ 0.1 Non-derivatives in ASC 815 net investment hedging relationships: Foreign currency denominated debt $ 0.9 Six Months Ended June 30, 2016 Amount of Gain (Loss) Recognized in OCI in Currency Translation Adjustments (Effective Portion) Derivatives in ASC 815 net investment hedging relationships: Cross-currency swap $ 0.1 Non-derivatives in ASC 815 net investment hedging relationships: Foreign currency denominated debt $ (0.5 ) Credit Risk Grace is exposed to credit risk in its trade accounts receivable. Customers in the petroleum refining industry represent the greatest exposure. Grace's credit evaluation policies mitigate credit risk exposures, and it has a history of minimal credit losses. Grace does not generally require collateral for its trade accounts receivable but may require a bank letter of credit in certain instances, particularly when selling to customers in cash-restricted countries. Grace may also be exposed to credit risk in its derivatives contracts. Grace monitors counterparty credit risk and currently does not anticipate nonperformance by counterparties to its derivatives. Grace's derivative contracts are with internationally recognized commercial financial institutions.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	The effective tax rate is 32.1% as of June 30, 2017 , compared with 35.6% for the year ended December 31, 2016 . The 2017 tax rate includes a discrete benefit of $3.0 million for share-based compensation deductions offset by a charge of $1.1 million for a tax law change in Tennessee. The 2016 tax rate included $10.1 million in discrete charges caused by an increase in the valuation allowance on deferred tax assets, partially offset by a discrete benefit of $6.7 million for share-based compensation deductions. Grace generated U.S. federal tax deductions relating to its emergence from bankruptcy in 2014. The deductions generated U.S. federal NOLs, which Grace has carried forward and expects to utilize in subsequent years. Under U.S. federal income tax law, a corporation is generally permitted to carry forward NOLs for a 20 -year period for deduction against future taxable income. Grace also generated U.S. federal tax deductions of $30 million upon payment of the ZAI PD obligation in the 2017 first quarter. (See Note 8.) The following table summarizes the balance of deferred tax assets, net of deferred tax liabilities, at June 30, 2017 , of $697.3 million : Deferred Tax Asset (Net of Liabilities) Valuation Allowance Net Deferred Tax Asset United States—Federal $ 627.1 $ (17.7 ) $ 609.4 United States—States 50.9 (11.2 ) 39.7 Germany 42.7 — 42.7 Other foreign 8.0 (2.5 ) 5.5 Total $ 728.7 $ (31.4 ) $ 697.3 Grace will need to generate approximately $1,700 million of U.S. federal taxable income by 2035 (or approximately $95 million per year during the carryforward period) to fully realize the U.S. federal net deferred tax assets. The following table summarizes expiration dates in jurisdictions where Grace has, or will have, material tax loss and credit carryforwards: Expiration Dates United States—Federal (NOLs) 2034 - 2035 United States—Federal (Credits) 2019 - 2027 United States—States (NOLs) 2017 - 2035 In evaluating its ability to realize its deferred tax assets, Grace considers all reasonably available positive and negative evidence, including recent earnings experience, expectations of future taxable income and the tax character of that income, the period of time over which the temporary differences become deductible and the carryforward and/or carryback periods available to Grace for tax reporting purposes in the related jurisdiction. In estimating future taxable income, Grace relies upon assumptions and estimates about future activities, including the amount of future federal, state and international pretax operating income that Grace will generate; the reversal of temporary differences; and the implementation of feasible and prudent tax planning strategies. Grace records a valuation allowance to reduce deferred tax assets to the amount that it believes is more likely than not to be realized.

Pension Plans and Other Postret

Pension Plans and Other Postretirement Benefit Plans	6 Months Ended
	Jun. 30, 2017
Pension and Other Postretirement Benefit Expense [Abstract]
Pension Plans and Other Postretirement Benefit Plans	Pension Plans The following table presents the funded status of Grace's underfunded and unfunded pension plans: (In millions) June 30, December 31, Underfunded defined benefit pension plans $ (81.5 ) $ (83.1 ) Unfunded defined benefit pension plans (362.7 ) (341.2 ) Total underfunded and unfunded defined benefit pension plans (444.2 ) (424.3 ) Pension liabilities included in other current liabilities (15.0 ) (14.4 ) Net funded status $ (459.2 ) $ (438.7 ) Underfunded plans include a group of advance-funded plans that are underfunded on a projected benefit obligation ("PBO") basis. Unfunded plans include several plans that are funded on a pay-as-you-go basis, and therefore, the entire PBO is unfunded. Components of Net Periodic Benefit Cost (Income) Three Months Ended June 30, 2017 2016 Pension Other Post Retirement Pension Other Post Retirement (In millions) U.S. Non-U.S. U.S. Non-U.S. Service cost $ 4.3 $ 2.0 $ — $ 4.4 $ 1.7 $ — Interest cost 10.5 1.1 — 10.2 1.3 — Expected return on plan assets (14.4 ) (0.2 ) — (14.2 ) (0.3 ) — Amortization of prior service credit (0.1 ) — (0.5 ) — — (0.6 ) Amortization of net deferred actuarial loss — — 0.1 — — 0.1 Curtailment gain — — — — (0.7 ) — Net periodic benefit cost (income) from continuing operations $ 0.3 $ 2.9 $ (0.4 ) $ 0.4 $ 2.0 $ (0.5 ) Six Months Ended June 30, 2017 2016 Pension Other Post Retirement Pension Other Post Retirement (In millions) U.S. Non-U.S. U.S. Non-U.S. Service cost $ 8.6 $ 4.0 $ — $ 9.4 $ 3.7 $ — Interest cost 21.0 2.1 — 20.7 3.3 — Expected return on plan assets (28.8 ) (0.4 ) — (28.8 ) (1.3 ) — Amortization of prior service credit (0.2 ) — (1.0 ) (0.1 ) — (1.2 ) Amortization of net deferred actuarial loss — — 0.2 — — 0.3 Curtailment gain — — — — (0.7 ) — Net periodic benefit cost (income) 0.6 5.7 (0.8 ) 1.2 5.0 (0.9 ) Less: discontinued operations — — — (0.5 ) (0.2 ) — Net periodic benefit cost (income) from continuing operations $ 0.6 $ 5.7 $ (0.8 ) $ 0.7 $ 4.8 $ (0.9 ) Plan Contributions and Funding Grace intends to satisfy its funding obligations under the U.S. qualified pension plans and to comply with all of the requirements of the Employee Retirement Income Security Act of 1974 ("ERISA"). For ERISA purposes, funded status is calculated on a different basis than under U.S. GAAP. Grace intends to fund non-U.S. pension plans based on applicable legal requirements and actuarial recommendations. Defined Contribution Retirement Plan Grace sponsors a defined contribution retirement plan for its employees in the United States. This plan is qualified under section 401(k) of the U.S. tax code. Currently, Grace contributes an amount equal to 100% of employee contributions, up to 6% of an individual employee's salary or wages. Grace's costs related to this benefit plan for the three and six months ended June 30, 2017 , were $3.0 million and $5.7 million compared with $2.7 million and $5.4 million for the corresponding prior-year periods. U.S. salaried employees and certain U.S. hourly employees that are hired on or after January 1, 2017, and employees in Germany that are hired on or after January 1, 2016, will participate in defined contribution plans instead of defined benefit pension plans.

Other Balance Sheet Accounts

Other Balance Sheet Accounts	6 Months Ended
	Jun. 30, 2017
Other Balance Sheet Accounts [Abstract]
Other Balance Sheet Accounts	(In millions) June 30, December 31, Other Current Liabilities Accrued compensation $ 39.0 $ 49.6 Environmental contingencies 26.8 32.5 Deferred revenue 21.2 27.2 Accrued interest 17.0 16.2 Pension liabilities 15.0 14.4 Income taxes payable 8.5 5.7 Other accrued liabilities 56.1 63.3 $ 183.6 $ 208.9 Accrued compensation includes salaries and wages as well as estimated current amounts due under the annual and long-term incentive programs. (In millions) June 30, December 31, Other Liabilities Environmental contingencies $ 41.5 $ 33.8 Liability to unconsolidated affiliate 27.4 27.0 Asset retirement obligation 8.7 10.2 Postemployment liability 7.0 7.2 Deferred revenue 9.4 2.3 Other noncurrent liabilities 59.6 46.2 $ 153.6 $ 126.7

Commitments and Contingent Liab

Commitments and Contingent Liabilities	6 Months Ended
	Jun. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingent Liabilities	Over the years, Grace operated numerous types of businesses that are no longer part of its business portfolio. As Grace divested or otherwise ceased operating these businesses, it retained certain liabilities and obligations, which we refer to as legacy liabilities. The principal legacy liabilities are product and environmental liabilities. Although the outcome of each of the matters discussed below cannot be predicted with certainty, Grace has assessed its risk and has made accounting estimates as required under U.S. GAAP. Legacy Product and Environmental Liabilities Legacy Product Liabilities Grace emerged from an asbestos-related Chapter 11 bankruptcy on February 3, 2014 (the "Effective Date"). Under its plan of reorganization, all pending and future asbestos-related claims are channeled for resolution to either a personal injury trust (the "PI Trust") or a property damage trust (the "PD Trust"). The trusts are the sole recourse for holders of asbestos-related claims. The channeling injunctions issued by the bankruptcy court prohibit holders of asbestos-related claims from asserting such claims directly against Grace. Grace has satisfied all of its financial obligations to the PI Trust. Grace has contingent financial obligations remaining to the PD Trust. With respect to property damage claims related to Grace’s former attic insulation product installed in the U.S. ("ZAI PD Claims"), the PD Trust was funded with $34.4 million on the Effective Date and $30.0 million on February 3, 2017. Grace is also obligated to make up to 10 contingent deferred payments of $8 million per year to the PD Trust in respect of ZAI PD Claims during the 20 -year period beginning on the fifth anniversary of the Effective Date, with each such payment due only if the assets of the PD Trust in respect of ZAI PD Claims fall below $10 million during the preceding year. Grace has not accrued for the 10 additional payments as Grace does not currently believe they are probable. Grace is not obligated to make additional payments to the PD Trust in respect of ZAI PD Claims beyond the payments described above. Grace has satisfied all of its financial obligations with respect to Canadian ZAI PD Claims. With respect to other asbestos property damage claims ("Other PD Claims"), claims unresolved as of the Effective Date are to be litigated in the bankruptcy court and any future claims are to be litigated in a federal district court, in each case pursuant to procedures approved by the bankruptcy court. To the extent any such Other PD Claims are determined to be allowed claims, they are to be paid in cash by the PD Trust. Grace is obligated to make a payment to the PD Trust every six months in the amount of any Other PD Claims allowed during the preceding six months plus interest (if applicable) and the amount of PD Trust expenses for the preceding six months (the "PD Obligation"). The aggregate amount to be paid under the PD Obligation is not capped and Grace may be obligated to make additional payments to the PD Trust in respect of the PD Obligation. Grace has accrued for those unresolved Other PD Claims that it believes are probable and estimable. Grace has not accrued for other unresolved or unasserted Other PD Claims as it does not believe that payment is probable. All payments to the PD Trust required after the Effective Date are secured by the Company's obligation to issue 77,372,257 shares of Company common stock to the PD Trust in the event of default, subject to customary anti-dilution provisions. This summary of the commitments and contingencies related to the Chapter 11 proceeding does not purport to be complete and is qualified in its entirety by reference to the plan of reorganization and the exhibits and documents related thereto, which have been filed with the SEC. Legacy Environmental Liabilities Grace is subject to loss contingencies resulting from extensive and evolving federal, state, local and foreign environmental laws and regulations relating to its manufacturing operations. Grace has procedures in place to minimize such contingencies; nevertheless, it has liabilities associated with past operations and additional claims may arise in the future. To address its legacy liabilities, Grace accrues for anticipated costs of response efforts where an assessment has indicated that a probable liability has been incurred and the cost can be reasonably estimated. These accruals do not take into account any discounting for the time value of money. Grace's environmental liabilities are reassessed regularly and adjusted when circumstances become better defined or response efforts and their costs can be better estimated, typically as a matter moves through the life-cycle of environmental investigation and remediation. These liabilities are evaluated based on currently available information, relating to the nature and extent of contamination, risk assessments, feasibility of response actions, and apportionment amongst other potentially responsible parties, all evaluated in light of prior experience. At June 30, 2017 , Grace's estimated liability for legacy environmental response costs totaled $68.3 million , compared with $66.3 million at December 31, 2016 , and was included in "other current liabilities" and "other liabilities" in the Consolidated Balance Sheets. These amounts are based on agreements in place or on Grace's estimate of costs where no formal remediation plan exists, yet there is sufficient information to estimate response costs. Vermiculite-Related Matters Grace purchased a vermiculite mine in Libby, Montana, in 1963 and operated it until 1990. Vermiculite concentrate from the Libby mine was used in the manufacture of attic insulation and other products. Some of the vermiculite ore contained naturally occurring asbestos. Grace is engaged with the U.S. Environmental Protection Agency (the "EPA") and other federal, state and local governmental agencies in a remedial investigation and feasibility study ("RI/FS") of the Libby mine and the surrounding area. In its 2017 Annual Project Update for the Libby Asbestos Superfund Site, the EPA announced a narrowing of its focus from the former "OU3 Study Area" to a smaller Operable Unit 3 or "OU3." Within this revised area, the RI/FS will determine the specific areas requiring remediation and will identify possible remedial action alternatives. Possible remedial actions within OU3 are wide-ranging, from institutional controls such as land use restrictions, to more active measures involving soil removal, containment projects, or other protective measures. Grace expects the RI/FS and a record of decision to be completed by the end of 2019. When meaningful new information becomes available, Grace will reevaluate estimated liability for the costs for remediation of the mine and surrounding area and adjust its reserves accordingly. The EPA is also investigating or remediating formerly owned or operated sites that processed Libby vermiculite into finished products. Grace is cooperating with the EPA on these investigation and remediation activities, and has recorded a liability to the extent that its review has indicated that a probable liability has been incurred and the cost is estimable. These liabilities cover the estimated cost of investigations and, to the extent an assessment has indicated that remediation is necessary, the estimable cost of response actions. Response actions typically involve soil excavation and removal, and replacement with clean fill. The EPA may commence additional investigations in the future at other sites that processed Libby vermiculite, but Grace does not believe, based on its knowledge of prior and current operations and site conditions, that liability for remediation at such other sites is probable. Grace accrued $4.3 million in the three months ended June 30, 2017 for future costs related to vermiculite-related matters, which reflects provision for an agreed upon remedy at a former vermiculite processing site. Grace's total estimated liability for response costs that are currently estimable for the Libby mine and surrounding area, and at vermiculite processing sites outside of Libby at June 30, 2017 , and December 31, 2016 , was $26.8 million and $31.2 million , respectively. It is probable that Grace's ultimate liability for these vermiculite-related matters will exceed current estimates by material amounts. Non-Vermiculite-Related Matters Grace accrued $8.9 million in the three months ended June 30, 2017 for future costs related to non-vermiculite-related matters, $7.2 million of which was to increase the liability for remediation at a former manufacturing site to maintain ten years of operation and maintenance expenses. At June 30, 2017 , and December 31, 2016 , Grace's estimated legacy environmental liability for response costs at sites not related to its former vermiculite mining and processing activities was $41.5 million and $35.1 million , respectively. This liability relates to Grace's former businesses or operations, including its share of liability at off-site disposal facilities. Grace's estimated liability is based upon regulatory requirements and environmental conditions at each site. As Grace receives new information its estimated liability may change materially. Commercial and Financial Commitments and Contingencies Purchase Commitments Grace uses purchase commitments to ensure supply and to minimize the volatility of major components of direct manufacturing costs including natural gas, certain metals, rare earths, and other materials. Such commitments are for quantities that Grace fully expects to use in its normal operations. Guarantees and Indemnification Obligations Grace is a party to many contracts containing guarantees and indemnification obligations. These contracts primarily consist of: • Product warranties with respect to certain products sold to customers in the ordinary course of business. These warranties typically provide that products will conform to specifications. Grace accrues a warranty liability on a transaction-specific basis depending on the individual facts and circumstances related to each sale. • Performance guarantees offered to customers under certain licensing arrangements. Grace has not established a liability for these arrangements based on past performance. • Licenses of intellectual property by Grace to third parties in which Grace has agreed to indemnify the licensee against third party infringement claims. • Contracts providing for the sale of a former business unit or product line in which Grace has agreed to indemnify the buyer against liabilities related to activities prior to the closing of the transaction, including environmental liabilities. • Contracts related to the Separation in which Grace has agreed to indemnify GCP against liabilities related to activities prior to the closing of the transaction, including tax, employee, and environmental liabilities. • Guarantees of real property lease obligations of third parties, typically arising out of (a) leases entered into by former subsidiaries of Grace, or (b) the assignment or sublease of a lease by Grace to a third party. Financial Assurances Financial assurances have been established for a variety of purposes, including insurance and environmental matters, trade-related commitments and other matters. At June 30, 2017 , Grace had gross financial assurances issued and outstanding of $122.9 million , composed of $39.5 million of surety bonds issued by various insurance companies and $83.4 million of standby letters of credit and other financial assurances issued by various banks.

Restructuring Expenses and Repo

Restructuring Expenses and Repositioning Expenses	6 Months Ended
	Jun. 30, 2017
Restructuring and Related Activities [Abstract]
Restructuring Expenses and Repositioning Expenses	Restructuring Expenses In the 2017 second quarter , Grace incurred costs from restructuring actions, primarily related to workforce reductions as a result of changes in the business environment and its business structure, which are included in "restructuring and repositioning expenses" in the Consolidated Statements of Operations. Costs in the 2016 first and second quarters primarily related to the exit of certain non-strategic product lines in the Materials Technologies reportable segment. The following table presents restructuring expenses by reportable segment for the three and six months ended June 30, 2017 . Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Catalysts Technologies $ — $ 0.6 $ 0.4 $ 1.1 Materials Technologies 0.1 7.3 0.3 15.2 Corporate 1.9 — 4.1 0.1 Total restructuring expenses $ 2.0 $ 7.9 $ 4.8 $ 16.4 These costs are not included in segment operating income. Substantially all costs related to the restructuring programs are expected to be paid by December 31, 2017. Restructuring Liability (In millions) Total Balance, December 31, 2016 $ 9.6 Accruals for severance and other costs 4.4 Payments (7.2 ) Currency translation adjustments and other 0.1 Balance, June 30, 2017 $ 6.9 Repositioning Expenses Pretax repositioning expenses included in continuing operations for the three and six months ended June 30, 2017 , were $3.3 million and $2.8 million compared with $1.5 million and $6.6 million for the corresponding prior-year periods . The expenses incurred in 2017 primarily relate to the Separation and third party consulting costs related to productivity initiatives. Substantially all of these costs have been or are expected to be settled in cash.

Other Expense (Income), net

Other Expense (Income), net	6 Months Ended
	Jun. 30, 2017
Other Income and Expenses [Abstract]
Other Expense (Income), net	Components of other (income) expense, net are as follows: Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Business interruption insurance recovery $ (10.6 ) $ — $ (13.1 ) $ — Currency transaction effects 1.5 (0.2 ) 2.0 0.3 Chapter 11 expenses, net 0.6 0.8 1.5 2.0 Interest income (0.6 ) (0.4 ) (0.8 ) (0.6 ) Net (gain) loss on sales of investments and disposals of assets 0.4 (0.3 ) 0.8 0.2 Loss on early extinguishment of debt — — — 11.1 Third-party acquisition-related costs — 2.5 — 2.5 Other miscellaneous (income) expense (0.9 ) 0.7 (2.2 ) (1.7 ) Total other (income) expense, net $ (9.6 ) $ 3.1 $ (11.8 ) $ 13.8 In January 2017, a Catalysts Technologies customer experienced an explosion and fire resulting in an extended outage. Grace has confirmed with its third party insurer that it has a valid claim under its business interruption insurance policy for lost profits as a result of the outage. The policy has a $25 million limit. Given the length of the outage, Grace expects to receive the full value of the policy by the end of 2017. Grace has received $10.4 million in payments from the insurer through June 30, 2017. See Note 3 for more information related to Grace's 2016 early extinguishment of debt.

Other Comprehensive Loss

Other Comprehensive Loss	6 Months Ended
	Jun. 30, 2017
Equity [Abstract]
Other Comprehensive Loss	The following tables present the pre-tax, tax, and after-tax components of Grace's other comprehensive income (loss) for the three and six months ended June 30, 2017 and 2016 : Three Months Ended June 30, 2017 Pre-Tax Amount Tax Benefit/ (Expense) After-Tax Amount Defined benefit pension and other postretirement plans: Amortization of net prior service credit included in net periodic benefit cost $ (0.6 ) $ 0.2 $ (0.4 ) Amortization of net deferred actuarial loss included in net periodic benefit cost 0.1 (0.1 ) — Benefit plans, net (0.5 ) 0.1 (0.4 ) Currency translation adjustments (8.3 ) — (8.3 ) Gain (loss) from hedging activities (0.2 ) — (0.2 ) Other comprehensive income (loss) attributable to W. R. Grace & Co. shareholders $ (9.0 ) $ 0.1 $ (8.9 ) Six Months Ended June 30, 2017 Pre-Tax Amount Tax Benefit/ (Expense) After-Tax Amount Defined benefit pension and other postretirement plans: Amortization of net prior service credit included in net periodic benefit cost $ (1.2 ) $ 0.4 $ (0.8 ) Amortization of net deferred actuarial loss included in net periodic benefit cost 0.2 (0.1 ) 0.1 Benefit plans, net (1.0 ) 0.3 (0.7 ) Currency translation adjustments (9.7 ) — (9.7 ) Gain (loss) from hedging activities 0.7 (0.2 ) 0.5 Other comprehensive income (loss) attributable to W. R. Grace & Co. shareholders $ (10.0 ) $ 0.1 $ (9.9 ) Three Months Ended June 30, 2016 Pre-Tax Amount Tax Benefit/ (Expense) After-Tax Amount Defined benefit pension and other postretirement plans: Amortization of net prior service credit included in net periodic benefit cost $ (0.6 ) $ 0.2 $ (0.4 ) Amortization of net deferred actuarial loss included in net periodic benefit cost 0.1 (0.1 ) — Benefit plans, net (0.5 ) 0.1 (0.4 ) Currency translation adjustments 1.3 — 1.3 Gain (loss) from hedging activities (0.4 ) 0.1 (0.3 ) Other comprehensive income (loss) attributable to W. R. Grace & Co. shareholders $ 0.4 $ 0.2 $ 0.6 Six Months Ended June 30, 2016 Pre-Tax Amount Tax Benefit/ (Expense) After-Tax Amount Defined benefit pension and other postretirement plans: Amortization of net prior service credit included in net periodic benefit cost $ (1.3 ) $ 0.5 $ (0.8 ) Amortization of net deferred actuarial loss included in net periodic benefit cost 0.3 (0.2 ) 0.1 Benefit plans, net (1.0 ) 0.3 (0.7 ) Currency translation adjustments (4.1 ) — (4.1 ) Gain (loss) from hedging activities (5.1 ) 1.8 (3.3 ) Other comprehensive income (loss) attributable to W. R. Grace & Co. shareholders $ (10.2 ) $ 2.1 $ (8.1 ) The following tables present the changes in accumulated other comprehensive income (loss), net of tax, for the six months ended June 30, 2017 and 2016 : Six Months Ended June 30, 2017 Defined Benefit Pension and Other Postretirement Plans Currency Translation Adjustments Gain (Loss) from Hedging Activities Total Beginning balance $ 2.2 $ 67.6 $ (3.4 ) $ 66.4 Other comprehensive income (loss) before reclassifications — (9.7 ) (0.7 ) (10.4 ) Amounts reclassified from accumulated other comprehensive income (loss) (0.7 ) — 1.2 0.5 Net current-period other comprehensive income (loss) (0.7 ) (9.7 ) 0.5 (9.9 ) Ending balance $ 1.5 $ 57.9 $ (2.9 ) $ 56.5 Six Months Ended June 30, 2016 Defined Benefit Pension and Other Postretirement Plans Currency Translation Adjustments Gain (Loss) from Hedging Activities Total Beginning balance $ 3.0 $ (66.1 ) $ (3.7 ) $ (66.8 ) Other comprehensive income (loss) before reclassifications — (4.1 ) (4.4 ) (8.5 ) Amounts reclassified from accumulated other comprehensive income (loss) (0.7 ) — 1.1 0.4 Net current-period other comprehensive income (loss) (0.7 ) (4.1 ) (3.3 ) (8.1 ) Distribution of GCP (0.2 ) 135.5 — 135.3 Ending balance $ 2.1 $ 65.3 $ (7.0 ) $ 60.4 Grace is a global enterprise operating in many countries with local currency generally deemed to be the functional currency for accounting purposes. The currency translation amount represents the adjustments necessary to translate the balance sheets valued in local currencies to the U.S. dollar as of the end of each period presented, and to translate revenues and expenses at average exchange rates for each period presented. See Note 4 for a discussion of hedging activities. See Note 6 for a discussion of pension plans and other postretirement benefit plans.

Earnings Per Share

Earnings Per Share	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Earnings Per Share	The following table shows a reconciliation of the numerators and denominators used in calculating basic and diluted earnings per share. Three Months Ended June 30, Six Months Ended June 30, (In millions, except per share amounts) 2017 2016 2017 2016 Numerators Income (loss) from continuing operations attributable to W. R. Grace & Co. shareholders $ 43.9 $ 38.1 $ 86.8 $ 48.5 Income (loss) from discontinued operations, net of income taxes — 0.6 — (9.3 ) Net income (loss) attributable to W. R. Grace & Co. shareholders $ 43.9 $ 38.7 $ 86.8 $ 39.2 Denominators Weighted average common shares—basic calculation 68.3 70.5 68.3 70.5 Dilutive effect of employee stock options 0.1 0.4 0.2 0.5 Weighted average common shares—diluted calculation 68.4 70.9 68.5 71.0 Basic earnings per share attributable to W. R. Grace & Co. shareholders Income (loss) from continuing operations $ 0.64 $ 0.54 $ 1.27 $ 0.69 Income (loss) from discontinued operations, net of income taxes — 0.01 — (0.13 ) Net income (loss) $ 0.64 $ 0.55 $ 1.27 $ 0.56 Diluted earnings per share attributable to W. R. Grace & Co. shareholders Income (loss) from continuing operations $ 0.64 $ 0.54 $ 1.27 $ 0.68 Income (loss) from discontinued operations, net of income taxes — 0.01 — (0.13 ) Net income (loss) $ 0.64 $ 0.55 $ 1.27 $ 0.55 There were 1.6 million and 1.5 million anti-dilutive options outstanding for the three and six months ended June 30, 2017 , compared with 1.0 million and 1.2 million for the corresponding prior-year periods . On February 5, 2015, the Company announced that its Board of Directors had authorized a share repurchase program of up to $500 million . During the six months ended June 30, 2017 and 2016 , the Company repurchased 425,673 shares and 472,400 shares of Company common stock for $30.0 million and $35.1 million , respectively, pursuant to the terms of the share repurchase program. As of June 30, 2017 , $3.9 million remained under this authorization. On February 8, 2017, the Company announced that its Board of Directors authorized a new share repurchase program of up to $250 million , expected to be completed over the next 24 to 36 months at the discretion of management. The timing of the repurchases and the actual amount repurchased will depend on a variety of factors, including the market price of the Company's shares, the strategic deployment of capital, and general market and economic conditions.

Operating Segment Information

Operating Segment Information	6 Months Ended
	Jun. 30, 2017
Segment Reporting [Abstract]
Operating Segment Information	Grace is a global producer of specialty chemicals and specialty materials. Grace's two reportable business segments are Grace Catalysts Technologies and Grace Materials Technologies. Grace Catalysts Technologies includes catalysts and related products and technologies used in refining, petrochemical and other chemical manufacturing applications. Advanced Refining Technologies (ART), Grace's joint venture with Chevron Products Company, a division of Chevron U.S.A. Inc. ("Chevron"), is managed in this segment. (See Note 14.) Grace Catalysts Technologies comprises two operating segments, Grace Refining Technologies and Grace Specialty Catalysts, which are aggregated into one reportable segment based upon similar economic characteristics, the nature of the products and production processes, type and class of customer, and channels of distribution. Grace Materials Technologies includes specialty materials, including silica-based and silica-alumina-based materials, used in coatings, consumer, industrial, and pharmaceutical applications. The table below presents information related to Grace's reportable segments. Only those corporate expenses directly related to the reportable segments are allocated for reporting purposes. All remaining corporate items are reported separately and labeled as such. Grace excludes defined benefit pension expense from the calculation of segment operating income. Grace believes that the exclusion of defined benefit pension expense provides a better indicator of its reportable segment performance as defined benefit pension expense is not managed at a reportable segment level. Grace defines Adjusted EBIT to be income from continuing operations attributable to W. R. Grace & Co. shareholders adjusted for interest income and expense; income taxes; costs related to legacy product, environmental and other claims; restructuring and repositioning expenses and asset impairments; pension costs other than service and interest costs, expected returns on plan assets, and amortization of prior service costs/credits; income and expense items related to divested businesses, product lines, and certain other investments; gains and losses on sales of businesses, product lines, and certain other investments; third-party acquisition-related costs and the amortization of acquired inventory fair value adjustment; and certain other items that are not representative of underlying trends. Reportable Segment Data Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Net Sales Catalysts Technologies $ 320.5 $ 278.4 $ 614.3 $ 539.0 Materials Technologies 109.0 112.1 213.2 214.3 Total $ 429.5 $ 390.5 $ 827.5 $ 753.3 Adjusted EBIT Catalysts Technologies segment operating income $ 101.3 $ 87.5 $ 182.5 $ 165.8 Materials Technologies segment operating income 24.2 28.0 49.0 48.6 Corporate costs (18.3 ) (16.3 ) (34.4 ) (29.5 ) Certain pension costs (3.2 ) (3.1 ) (6.3 ) (6.2 ) Total $ 104.0 $ 96.1 $ 190.8 $ 178.7 Corporate costs include corporate support function costs and other corporate costs such as professional fees and insurance premiums. Certain pension costs include only ongoing costs recognized quarterly, which include service and interest costs, expected returns on plan assets, and amortization of prior service costs/credits. Reconciliation of Reportable Segment Data to Financial Statements Grace Adjusted EBIT for the three and six months ended June 30, 2017 and 2016 , is reconciled below to income from continuing operations before income taxes presented in the accompanying Consolidated Statements of Operations. Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Grace Adjusted EBIT $ 104.0 $ 96.1 $ 190.8 $ 178.7 (Costs) benefit related to legacy product, environmental and other claims (14.9 ) (6.7 ) (17.0 ) (11.1 ) Restructuring and repositioning expenses (5.4 ) (9.4 ) (7.7 ) (23.0 ) Pension MTM adjustment and other related costs, net — 0.7 (1.9 ) 0.9 Income and expense items related to divested businesses (0.7 ) 0.1 (1.0 ) (0.2 ) Third-party acquisition-related costs — (2.5 ) — (2.5 ) Gain on sale of product line — 0.7 — 0.7 Loss on early extinguishment of debt — — — (11.1 ) Interest expense, net (19.5 ) (19.4 ) (38.8 ) (41.2 ) Net income (loss) attributable to noncontrolling interests (0.4 ) (0.2 ) (0.4 ) (0.4 ) Income from continuing operations before income taxes $ 63.1 $ 59.4 $ 124.0 $ 90.8 Geographic Area Data The table below presents information related to the geographic areas in which Grace operates. Sales are attributed to geographic areas based on customer location. Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Net Sales United States $ 108.8 $ 112.4 $ 212.6 $ 220.6 Canada and Puerto Rico 12.0 11.6 23.9 22.3 Total North America 120.8 124.0 236.5 242.9 Europe Middle East Africa 163.9 158.4 312.6 300.8 Asia Pacific 115.5 83.1 215.4 155.2 Latin America 29.3 25.0 63.0 54.4 Total $ 429.5 $ 390.5 $ 827.5 $ 753.3

Unconsolidated Affiliate

Unconsolidated Affiliate	6 Months Ended
	Jun. 30, 2017
Equity Method Investments and Joint Ventures [Abstract]
Unconsolidated Affiliate	Grace accounts for its 50% ownership interest in ART, its joint venture with Chevron, using the equity method of accounting. Grace's investment in ART amounted to $131.9 million and $117.6 million as of June 30, 2017 , and December 31, 2016 , respectively, and the amount included in "equity in earnings of unconsolidated affiliate" in the accompanying Consolidated Statements of Operations totaled $6.1 million and $13.1 million for the three and six months ended June 30, 2017 , compared with $2.6 million and $9.5 million for the corresponding prior-year periods . ART is a private, limited liability company, taxed as a partnership, and accordingly does not have a quoted market price available. The following summary presents ART's assets, liabilities and results of operations. (In millions) June 30, December 31, 2016 Summary Balance Sheet information: Current assets $ 246.7 $ 249.2 Noncurrent assets 84.9 84.8 Total assets $ 331.6 $ 334.0 Current liabilities $ 71.7 $ 102.0 Noncurrent liabilities — 0.3 Total liabilities $ 71.7 $ 102.3 Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Net sales $ 110.5 $ 81.7 $ 207.9 $ 145.7 Costs and expenses applicable to net sales 94.7 75.2 173.6 123.4 Income before income taxes 12.6 5.3 26.8 19.2 Net income 12.2 5.1 26.2 18.9 Grace and ART transact business on a regular basis and maintain several agreements in order to operate the joint venture. These agreements are treated as related party activities with an unconsolidated affiliate. Sales to ART are accounted for on a net basis, with a mark-up, in "cost of goods sold" in the Consolidated Statements of Operations. Grace also receives reimbursement from ART for fixed costs, research and development, selling, general and administrative services and depreciation. Grace records reimbursements against the respective line items on Grace's Consolidated Statement of Operations. The table below presents summary financial data related to transactions between Grace and ART. Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Grace sales of catalysts to ART $ 53.1 $ 43.8 $ 104.5 $ 100.3 Mark-up on Grace's sales to ART included as a reduction of Grace's cost of goods sold 1.0 1.1 2.0 2.0 Charges for fixed costs, research and development, selling, general and administrative services, and depreciation to ART 10.4 6.1 20.8 12.3 The table below lists Grace balances related to ART. (in millions) June 30, December 31, Accounts receivable $ 3.3 $ 14.9 Noncurrent asset 27.4 27.0 Accounts payable 28.8 28.7 Debt payable within one year 7.8 7.6 Debt payable after one year 32.2 31.9 Noncurrent liability 27.4 27.0 The noncurrent asset and noncurrent liability in the table above represent spending to date related to a planned residue hydroprocessing catalyst production plant in Lake Charles, Louisiana. Grace manages the design and construction of the plant, and the asset will be included in "other assets" in Grace's Consolidated Balance Sheets until construction is completed. Grace has likewise recorded a liability for the transfer of the asset to ART upon completion, included in "other liabilities" in the Consolidated Balance Sheets. Grace and Chevron provide lines of credit in the amount of $15.0 million each at a commitment fee of 0.1% of the credit amount. These agreements have been approved by the ART Executive Committee for renewal until February 24, 2018. No amounts were outstanding at June 30, 2017 , and December 31, 2016 .

Discontinued Operations

Discontinued Operations	6 Months Ended
	Jun. 30, 2017
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	As a result of the Separation and Distribution, GCP is now an independent public company and its common stock is listed under the symbol "GCP" on the New York Stock Exchange. Grace does not beneficially own any shares of GCP common stock and will not consolidate the financial results of GCP in its future financial reporting, as GCP is no longer a related party to Grace subsequent to the Separation. GCP’s historical financial results through the Distribution Date are reflected in Grace’s Consolidated Financial Statements as discontinued operations. For a summary of the Separation and Distribution Agreement and the related Tax Sharing Agreement, see Note 21, "Discontinued Operations" to the Consolidated Financial Statements in Grace's Form 10-K for the year ended December 31, 2016. Grace has filed the full texts of the Separation and Distribution Agreement and the Tax Sharing Agreement with the SEC, which are readily available on the Internet at www.sec.gov. GCP's historical financial results through the February 3, 2016, Distribution Date and other effects of the Separation for the six months ended June 30, 2016, are presented as discontinued operations as summarized below: Six Months Ended June 30, (In millions) 2016 Net sales $ 99.6 Cost of goods sold 62.6 Gross profit 37.0 Selling, general and administrative expenses 21.6 Research and development expenses 1.7 Repositioning expenses 22.0 Interest expense and related financing costs 0.7 Other expense, net 3.9 Total costs and expenses 49.9 (Loss) Income from discontinued operations before income taxes (12.9 ) Benefit from (provision for) income taxes 3.7 (Loss) Income from discontinued operations after income taxes (9.2 ) Less: Net income attributable to noncontrolling interests (0.1 ) Net (loss) income from discontinued operations $ (9.3 ) In January 2016, GCP completed the sale of $525.0 million aggregate principal amount of 9.500% Senior Notes due in 2023. GCP used a portion of these proceeds to fund a $500.0 million distribution to Grace in connection with the Separation and the Distribution. In February 2016, GCP entered into a credit agreement that provides for new senior secured credit facilities in an aggregate principal amount of $525.0 million , consisting of term loans in an aggregate principal amount of $275.0 million maturing in 2022 and of revolving loans in an aggregate principal amount of $250.0 million maturing in 2021, which were undrawn at closing. GCP used a portion of these proceeds to fund a $250.0 million distribution to Grace in connection with the Separation and the Distribution.

Basis of Presentation and Sum23

Basis of Presentation and Summary of Significant Accounting and Financial Reporting Policies (Policies)	6 Months Ended
	Jun. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The interim Consolidated Financial Statements presented herein are unaudited and should be read in conjunction with the Consolidated Financial Statements presented in the Company's 2016 Annual Report on Form 10-K. Such interim Consolidated Financial Statements reflect all adjustments that, in the opinion of management, are necessary for a fair statement of the results of the interim periods presented; all such adjustments are of a normal recurring nature except for the impacts of adopting new accounting standards as discussed below. All significant intercompany accounts and transactions have been eliminated.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles ("U.S. GAAP") requires management to make estimates and assumptions that affect the reported amount of assets and liabilities and disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements, and the reported amounts of revenues and expenses for the periods presented. Actual amounts could differ from those estimates, and the differences could be material. Changes in estimates are recorded in the period identified. Grace's accounting measurements that are most affected by management's estimates of future events are: • Realization values of net deferred tax assets, which depend on projections of future taxable income (see Note 5); • Pension and postretirement liabilities, which depend on assumptions regarding participant life spans, future inflation, discount rates and total returns on invested funds (see Note 6); • Carrying values of goodwill and other intangible assets, which depend on assumptions of future earnings and cash flows; and • Contingent liabilities, which depend on an assessment of the probability of loss and an estimate of ultimate obligation, such as litigation (see Note 8), income taxes (see Note 5), and environmental remediation (see Note 8).
Reclassifications	Reclassifications Certain amounts in prior years' Consolidated Financial Statements have been reclassified to conform to the current year presentation. Such reclassifications have not materially affected previously reported amounts in the Consolidated Financial Statements.
Effect of New Accounting Standards	Recently Issued Accounting Standards In May 2014, the FASB issued ASU 2014-09 "Revenue from Contracts with Customers." This update is intended to remove inconsistencies and weaknesses in revenue requirements; provide a more robust framework for addressing revenue issues; improve comparability of revenue recognition practices across entities, industries, jurisdictions and capital markets; provide more useful information to users of financial statements through improved disclosure requirements; and simplify the preparation of financial statements by reducing the number of requirements to which an entity must refer. The new requirements are effective for fiscal years beginning after December 15, 2017, and for interim periods within those fiscal years, with early adoption permitted for fiscal years beginning after December 15, 2016. The standard allows for two methods of adoption: (a) full retrospective adoption, meaning the standard is applied to all periods presented, or (b) modified retrospective adoption, meaning the cumulative effect of applying the new standard is recognized as an adjustment to the opening retained earnings balance. Grace will adopt the standard in the 2018 first quarter. Grace has begun its preliminary assessment and is identifying specific areas of impact on the Consolidated Financial Statements. At this time, Grace cannot reasonably estimate the effect of adoption. Grace has tentatively decided to adopt this standard under the modified retrospective approach and is still evaluating the effect on its financial statements and disclosures. In February 2016, the FASB issued ASU 2016-02 "Leases (Topic 842)." This update is intended to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. The core principle of Topic 842 is that a lessee should recognize the assets and liabilities that arise from leases. A lessee should recognize in the statement of financial position a liability to make lease payments (the lease liability) and a right-of-use asset representing its right to use the underlying asset for the lease term, including optional payments where they are reasonably certain to occur. The amendments in this update are effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, with early adoption permitted. Currently, as a lessee, Grace is a party to a number of leases which, under existing guidance, are classified as operating leases and not recorded on the balance sheet but are expensed as incurred. Under the new standard, many of these leases will be recorded on the Consolidated Balance Sheets. Grace will adopt the standard in 2019 and at this time cannot reasonably estimate the effect of adoption. In November 2016, the FASB issued ASU 2016-18 "Statement of Cash Flows (Topic 230): Restricted Cash," which requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash or restricted cash equivalents. Therefore, amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. The new requirements are effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years, with early adoption permitted. Grace is currently evaluating the timing of adoption and does not expect the update to have a material effect on the Consolidated Financial Statements. As of June 30, 2017 , and December 31, 2016 , restricted cash included in the Consolidated Balance Sheets was $10.8 million and $10.0 million , respectively. In January 2017, the FASB issued ASU 2017-01 "Business Combinations (Topic 805)," which provides a screen to determine when an integrated set of assets and activities is not a business. The screen requires that when substantially all of the fair value of the gross assets acquired (or disposed of) is concentrated in a single identifiable asset or a group of similar identifiable assets, the set is not a business. This screen reduces the number of transactions that need to be further evaluated. If the screen is not met, the amendments in this update (1) require that to be considered a business, a set must include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create output and (2) remove the evaluation of whether a market participant could replace missing elements. The amendments in this update also narrow the definition of the term "output" so that the term is consistent with how outputs are described in Topic 606. Public business entities are required to apply the amendments in this update to annual periods beginning after December 15, 2017, including interim periods within those periods. Early application is permitted. Grace will evaluate the effect of the update at the time of any future acquisition or disposal. In January 2017, the FASB issued ASU 2017-04 "Intangibles—Goodwill and Other (Topic 350)." This update modifies the concept of impairment from the condition that exists when the carrying amount of goodwill exceeds its implied fair value to the condition that exists when the carrying amount of a reporting unit exceeds its fair value. An entity no longer will determine goodwill impairment by calculating the implied fair value of goodwill by assigning the fair value of a reporting unit to all of its assets and liabilities as if that reporting unit had been acquired in a business combination ("Step 2"). Because these amendments eliminate Step 2 from the goodwill impairment test, they should reduce the cost and complexity of evaluating goodwill for impairment. Public business entities are required to adopt the amendments in this update for annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. Grace is currently evaluating the timing of adoption and does not expect the update to have a material effect on the Consolidated Financial Statements. In March 2017, the FASB issued ASU 2017-07 "Compensation—Retirement Benefits (Topic 715)." This update requires that the service cost component of net benefit cost be presented with other compensation costs arising from services rendered. The remaining net benefit cost is either presented as a line item in the statement of operations outside of a subtotal for income from operations, if presented, or disclosed separately. Only the service cost component of net benefit expense can be capitalized. Public business entities are required to adopt the amendments in this update for fiscal years beginning after December 15, 2017. Grace is currently evaluating the update's effect on the Consolidated Financial Statements and will adopt the update in the 2018 first quarter. In May 2017, the FASB issued ASU 2017-09 "Compensation—Stock Compensation (Topic 718)." This update clarifies the existing definition of the term "modification," which is currently defined as "a change in any of the terms or conditions of a share-based payment award." The update requires entities to account for modifications of share-based payment awards unless the (1) fair value, (2) vesting conditions and (3) classification as an equity instrument or a liability instrument of the modified award are the same as of the original award before modification. Public business entities are required to adopt the amendments in this update for fiscal years and interim periods beginning after December 15, 2017, with early adoption permitted. Grace does not currently have any modifications of share-based awards and will adopt the update when it becomes effective. Recently Adopted Accounting Standards In July 2015, the FASB issued ASU 2015-11 "Simplifying the Measurement of Inventory." This update is part of the FASB's Simplification Initiative and is also intended to enhance convergence with the International Accounting Standards Board's ("IASB") measurement of inventory. The update requires that inventory be measured at the lower of cost or net realizable value for entities using FIFO (first-in, first-out) or average cost methods. The new requirements are effective for fiscal years beginning after December 15, 2016, and for interim periods within those fiscal years, with early adoption permitted. Grace adopted this update in the first quarter of 2017, and it did not have a material effect on the Consolidated Financial Statements. In August 2016, the FASB issued ASU 2016-15 "Classification of Certain Cash Receipts and Cash Payments." This update is intended to reduce diversity in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. It addresses eight specific issues. The amendments in this update are effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years, with early adoption permitted. Grace adopted this update in the 2017 second quarter, and it did not have a material effect on the Consolidated Financial Statements.

Inventories (Tables)

Inventories (Tables)	6 Months Ended
	Jun. 30, 2017
Inventory Disclosure [Abstract]
Schedule of inventories	Inventories consisted of the following at June 30, 2017 , and December 31, 2016 : (In millions) June 30, December 31, Raw materials $ 55.3 $ 57.7 In process 36.0 33.4 Finished products 123.1 115.8 Other 22.1 21.1 $ 236.5 $ 228.0

Debt (Tables)

Debt (Tables)	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Disclosure of debt	Components of Debt (In millions) June 30, December 31, 5.125% senior notes due 2021, net of unamortized debt issuance costs of $6.6 at June 30, 2017 (2016—$7.3) $ 693.4 $ 692.7 U.S. dollar term loan, net of unamortized debt issuance costs and discounts of $5.1 at June 30, 2017 (2016—$5.7) 403.3 402.7 5.625% senior notes due 2024, net of unamortized debt issuance costs of $3.7 at June 30, 2017 (2016—$4.0) 296.3 296.0 Euro term loan, net of unamortized debt issuance costs and discounts of $1.1 at June 30, 2017 (2016—$1.3) 89.9 82.5 Revolving credit facility 40.0 — Debt payable to unconsolidated affiliate 40.0 39.5 Deferred payment obligation — 30.0 Other borrowings(1) 40.1 40.7 Total debt 1,603.0 1,584.1 Less debt payable within one year 86.5 76.5 Debt payable after one year $ 1,516.5 $ 1,507.6 Weighted average interest rates on total debt 4.6 % 4.6 % ___________________________________________________________________________________________________________________ (1) Represents borrowings under various lines of credit and other borrowings, primarily by non-U.S. subsidiaries.
Schedule of Maturities of Long-term Debt	The principal maturities of debt outstanding at June 30, 2017 , were as follows: (In millions) 2017 $ 82.4 2018 8.4 2019 7.8 2020 6.6 2021 1,191.7 Thereafter 306.1 Total debt $ 1,603.0

Fair Value Measurements and R26

Fair Value Measurements and Risk (Tables)	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Schedule of Carrying Values and Estimated Fair Values of Debt Instruments	At June 30, 2017 , the carrying amounts and fair values of Grace's debt were as follows: June 30, 2017 December 31, 2016 (In millions) Carrying Amount Fair Value Carrying Amount Fair Value 5.125% senior notes due 2021(1) $ 693.4 $ 745.4 $ 692.7 $ 721.3 U.S. dollar term loan(2) 403.3 402.8 402.7 408.2 5.625% senior notes due 2024(1) 296.3 318.5 296.0 311.5 Euro term loan(2) 89.9 89.9 82.5 82.0 Other borrowings 120.1 120.1 110.2 110.2 Total debt $ 1,603.0 $ 1,676.7 $ 1,584.1 $ 1,633.2 ___________________________________________________________________________________________________________________ (1) Carrying amounts are net of unamortized debt issuance costs of $6.6 million and $3.7 million as of June 30, 2017 , and $7.3 million and $4.0 million as of December 31, 2016 , related to the 5.125% senior notes due 2021 and 5.625% senior notes due 2024, respectively. (2) Carrying amounts are net of unamortized debt issuance costs and discounts of $5.1 million and $1.1 million as of June 30, 2017 , and $5.7 million and $1.3 million as of December 31, 2016 , related to the U.S. dollar term loan and euro term loan, respectively.
Schedule of Fair Value of Assets and Liabilities Measured on a Recurring Basis	The following tables present the fair value hierarchy for financial assets and liabilities measured at fair value on a recurring basis as of June 30, 2017 , and December 31, 2016 : Fair Value Measurements at June 30, 2017, Using (In millions) Total Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Currency derivatives $ 3.6 $ — $ 3.6 $ — Total Assets $ 3.6 $ — $ 3.6 $ — Liabilities Interest rate derivatives $ 5.1 $ — $ 5.1 $ — Currency derivatives 11.6 — 11.6 — Total Liabilities $ 16.7 $ — $ 16.7 $ — Fair Value Measurements at December 31, 2016, Using (In millions) Total Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Currency derivatives $ 8.8 $ — $ 8.8 $ — Total Assets $ 8.8 $ — $ 8.8 $ — Liabilities Interest rate derivatives $ 6.0 $ — $ 6.0 $ — Currency derivatives 0.9 — 0.9 — Total Liabilities $ 6.9 $ — $ 6.9 $ —
Schedule of the Location and Fair Values of Derivative Instruments Included in the Consolidated Balance Sheets	The following tables present the location and fair values of derivative instruments included in the Consolidated Balance Sheets as of June 30, 2017 , and December 31, 2016 : June 30, 2017 Asset Derivatives Liability Derivatives Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as hedging instruments under ASC 815: Currency contracts Other current assets $ 3.0 Other current liabilities $ 0.4 Interest rate contracts Other current assets — Other current liabilities 1.9 Currency contracts Other assets — Other liabilities 10.5 Interest rate contracts Other assets — Other liabilities 3.2 Derivatives not designated as hedging instruments under ASC 815: Currency contracts Other current assets 0.6 Other current liabilities 0.7 Total derivatives $ 3.6 $ 16.7 December 31, 2016 Asset Derivatives Liability Derivatives Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as hedging instruments under ASC 815: Currency contracts Other current assets $ 4.0 Other current liabilities $ — Interest rate contracts Other current assets — Other current liabilities 2.8 Currency contracts Other assets 4.0 Other liabilities — Interest rate contracts Other assets — Other liabilities 3.2 Derivatives not designated as hedging instruments under ASC 815: Currency contracts Other current assets 0.8 Other current liabilities 0.9 Total derivatives $ 8.8 $ 6.9
Schedule of Gain (Loss) on Derivative Instruments	The following tables present the location and amount of gains and losses on derivative instruments included in the Consolidated Statements of Operations or, when applicable, gains and losses initially recognized in other comprehensive income (loss) ("OCI") for the three and six months ended June 30, 2017 and 2016 : Three Months Ended June 30, 2017 Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from OCI into Income (Effective Portion) Derivatives in ASC 815 cash flow hedging relationships: Interest rate contracts $ (1.1 ) Interest expense $ (0.8 ) Currency contracts — Other expense (0.1 ) Total derivatives $ (1.1 ) $ (0.9 ) Six Months Ended June 30, 2017 Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from OCI into Income (Effective Portion) Derivatives in ASC 815 cash flow hedging relationships: Interest rate contracts $ (1.0 ) Interest expense $ (1.7 ) Currency contracts (0.1 ) Other expense (0.1 ) Total derivatives $ (1.1 ) $ (1.8 ) Three Months Ended June 30, 2016 Amount of Gain (Loss) Recognized in OCI on Derivatives Location of Gain (Loss) Reclassified from Accumulated OCI into Income Amount of Gain (Loss) Reclassified from OCI into Income Derivatives in ASC 815 cash flow hedging relationships: Interest rate contracts $ (1.9 ) Interest expense $ (1.1 ) Currency contracts 0.2 Other expense (0.1 ) Total derivatives $ (1.7 ) $ (1.2 ) Six Months Ended June 30, 2016 Amount of Gain (Loss) Recognized in OCI on Derivatives Location of Gain (Loss) Reclassified from Accumulated OCI into Income Amount of Gain (Loss) Reclassified from OCI into Income Derivatives in ASC 815 cash flow hedging relationships: Interest rate contracts $ (6.4 ) Interest expense $ (2.1 ) Currency contracts 0.1 Other expense 0.4 Total derivatives $ (6.3 ) $ (1.7 )
Schedule of Gain (Loss) on Nonderivative Instruments	The following tables present the location and amount of gains and losses on derivative and non-derivative instruments designated as net investment hedges for the three and six months ended June 30, 2017 and 2016 . There were no reclassifications of the effective portion of net investment hedges out of OCI and into earnings for the periods presented in the tables below. Three Months Ended June 30, 2017 Amount of Gain (Loss) Recognized in OCI in Currency Translation Adjustments (Effective Portion) Derivatives in ASC 815 net investment hedging relationships: Cross-currency swap $ (6.1 ) Non-derivatives in ASC 815 net investment hedging relationships: Foreign currency denominated debt $ (4.9 ) Foreign currency denominated deferred intercompany royalties (2.9 ) $ (7.8 ) Six Months Ended June 30, 2017 Amount of Gain (Loss) Recognized in OCI in Currency Translation Adjustments (Effective Portion) Derivatives in ASC 815 net investment hedging relationships: Cross-currency swap $ (8.6 ) Non-derivatives in ASC 815 net investment hedging relationships: Foreign currency denominated debt $ (7.2 ) Foreign currency denominated deferred intercompany royalties (4.4 ) $ (11.6 ) Three Months Ended June 30, 2016 Amount of Gain (Loss) Recognized in OCI in Currency Translation Adjustments (Effective Portion) Derivatives in ASC 815 net investment hedging relationships: Cross-currency swap $ 0.1 Non-derivatives in ASC 815 net investment hedging relationships: Foreign currency denominated debt $ 0.9 Six Months Ended June 30, 2016 Amount of Gain (Loss) Recognized in OCI in Currency Translation Adjustments (Effective Portion) Derivatives in ASC 815 net investment hedging relationships: Cross-currency swap $ 0.1 Non-derivatives in ASC 815 net investment hedging relationships: Foreign currency denominated debt $ (0.5 )

Income Taxes (Tables)

Income Taxes (Tables)	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Schedule of Deferred Tax Assets and Liabilities	The following table summarizes the balance of deferred tax assets, net of deferred tax liabilities, at June 30, 2017 , of $697.3 million : Deferred Tax Asset (Net of Liabilities) Valuation Allowance Net Deferred Tax Asset United States—Federal $ 627.1 $ (17.7 ) $ 609.4 United States—States 50.9 (11.2 ) 39.7 Germany 42.7 — 42.7 Other foreign 8.0 (2.5 ) 5.5 Total $ 728.7 $ (31.4 ) $ 697.3
Summary of Operating Loss Carryforwards	The following table summarizes expiration dates in jurisdictions where Grace has, or will have, material tax loss and credit carryforwards: Expiration Dates United States—Federal (NOLs) 2034 - 2035 United States—Federal (Credits) 2019 - 2027 United States—States (NOLs) 2017 - 2035

Pension Plans and Other Postr28

Pension Plans and Other Postretirement Benefit Plans (Tables)	6 Months Ended
	Jun. 30, 2017
Pension plans and other postretirement benefit plans
Schedule of net funded status of fully funded, underfunded, and unfunded pension plans	The following table presents the funded status of Grace's underfunded and unfunded pension plans: (In millions) June 30, December 31, Underfunded defined benefit pension plans $ (81.5 ) $ (83.1 ) Unfunded defined benefit pension plans (362.7 ) (341.2 ) Total underfunded and unfunded defined benefit pension plans (444.2 ) (424.3 ) Pension liabilities included in other current liabilities (15.0 ) (14.4 ) Net funded status $ (459.2 ) $ (438.7 )
Components of net periodic benefit cost (income)	Three Months Ended June 30, 2017 2016 Pension Other Post Retirement Pension Other Post Retirement (In millions) U.S. Non-U.S. U.S. Non-U.S. Service cost $ 4.3 $ 2.0 $ — $ 4.4 $ 1.7 $ — Interest cost 10.5 1.1 — 10.2 1.3 — Expected return on plan assets (14.4 ) (0.2 ) — (14.2 ) (0.3 ) — Amortization of prior service credit (0.1 ) — (0.5 ) — — (0.6 ) Amortization of net deferred actuarial loss — — 0.1 — — 0.1 Curtailment gain — — — — (0.7 ) — Net periodic benefit cost (income) from continuing operations $ 0.3 $ 2.9 $ (0.4 ) $ 0.4 $ 2.0 $ (0.5 ) Six Months Ended June 30, 2017 2016 Pension Other Post Retirement Pension Other Post Retirement (In millions) U.S. Non-U.S. U.S. Non-U.S. Service cost $ 8.6 $ 4.0 $ — $ 9.4 $ 3.7 $ — Interest cost 21.0 2.1 — 20.7 3.3 — Expected return on plan assets (28.8 ) (0.4 ) — (28.8 ) (1.3 ) — Amortization of prior service credit (0.2 ) — (1.0 ) (0.1 ) — (1.2 ) Amortization of net deferred actuarial loss — — 0.2 — — 0.3 Curtailment gain — — — — (0.7 ) — Net periodic benefit cost (income) 0.6 5.7 (0.8 ) 1.2 5.0 (0.9 ) Less: discontinued operations — — — (0.5 ) (0.2 ) — Net periodic benefit cost (income) from continuing operations $ 0.6 $ 5.7 $ (0.8 ) $ 0.7 $ 4.8 $ (0.9 )

Other Balance Sheet Accounts (T

Other Balance Sheet Accounts (Tables)	6 Months Ended
	Jun. 30, 2017
Other Balance Sheet Accounts [Abstract]
Schedule of Other Assets and Other Liabilities	(In millions) June 30, December 31, Other Current Liabilities Accrued compensation $ 39.0 $ 49.6 Environmental contingencies 26.8 32.5 Deferred revenue 21.2 27.2 Accrued interest 17.0 16.2 Pension liabilities 15.0 14.4 Income taxes payable 8.5 5.7 Other accrued liabilities 56.1 63.3 $ 183.6 $ 208.9 Accrued compensation includes salaries and wages as well as estimated current amounts due under the annual and long-term incentive programs. (In millions) June 30, December 31, Other Liabilities Environmental contingencies $ 41.5 $ 33.8 Liability to unconsolidated affiliate 27.4 27.0 Asset retirement obligation 8.7 10.2 Postemployment liability 7.0 7.2 Deferred revenue 9.4 2.3 Other noncurrent liabilities 59.6 46.2 $ 153.6 $ 126.7

Restructuring Expenses and Re30

Restructuring Expenses and Repositioning Expenses (Tables)	6 Months Ended
	Jun. 30, 2017
Restructuring and Related Activities [Abstract]
Schedule of restructuring expenses and asset impairments	The following table presents restructuring expenses by reportable segment for the three and six months ended June 30, 2017 . Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Catalysts Technologies $ — $ 0.6 $ 0.4 $ 1.1 Materials Technologies 0.1 7.3 0.3 15.2 Corporate 1.9 — 4.1 0.1 Total restructuring expenses $ 2.0 $ 7.9 $ 4.8 $ 16.4
Schedule of restructuring liability	Restructuring Liability (In millions) Total Balance, December 31, 2016 $ 9.6 Accruals for severance and other costs 4.4 Payments (7.2 ) Currency translation adjustments and other 0.1 Balance, June 30, 2017 $ 6.9

Other Expense (Income), net (Ta

Other Expense (Income), net (Tables)	6 Months Ended
	Jun. 30, 2017
Other Income and Expenses [Abstract]
Schedule of other (income) expense, net	Components of other (income) expense, net are as follows: Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Business interruption insurance recovery $ (10.6 ) $ — $ (13.1 ) $ — Currency transaction effects 1.5 (0.2 ) 2.0 0.3 Chapter 11 expenses, net 0.6 0.8 1.5 2.0 Interest income (0.6 ) (0.4 ) (0.8 ) (0.6 ) Net (gain) loss on sales of investments and disposals of assets 0.4 (0.3 ) 0.8 0.2 Loss on early extinguishment of debt — — — 11.1 Third-party acquisition-related costs — 2.5 — 2.5 Other miscellaneous (income) expense (0.9 ) 0.7 (2.2 ) (1.7 ) Total other (income) expense, net $ (9.6 ) $ 3.1 $ (11.8 ) $ 13.8

Other Comprehensive Loss (Table

Other Comprehensive Loss (Tables)	6 Months Ended
	Jun. 30, 2017
Equity [Abstract]
Disclosure of pre-tax, tax, and after-tax components of other comprehensive income (loss)	The following tables present the pre-tax, tax, and after-tax components of Grace's other comprehensive income (loss) for the three and six months ended June 30, 2017 and 2016 : Three Months Ended June 30, 2017 Pre-Tax Amount Tax Benefit/ (Expense) After-Tax Amount Defined benefit pension and other postretirement plans: Amortization of net prior service credit included in net periodic benefit cost $ (0.6 ) $ 0.2 $ (0.4 ) Amortization of net deferred actuarial loss included in net periodic benefit cost 0.1 (0.1 ) — Benefit plans, net (0.5 ) 0.1 (0.4 ) Currency translation adjustments (8.3 ) — (8.3 ) Gain (loss) from hedging activities (0.2 ) — (0.2 ) Other comprehensive income (loss) attributable to W. R. Grace & Co. shareholders $ (9.0 ) $ 0.1 $ (8.9 ) Six Months Ended June 30, 2017 Pre-Tax Amount Tax Benefit/ (Expense) After-Tax Amount Defined benefit pension and other postretirement plans: Amortization of net prior service credit included in net periodic benefit cost $ (1.2 ) $ 0.4 $ (0.8 ) Amortization of net deferred actuarial loss included in net periodic benefit cost 0.2 (0.1 ) 0.1 Benefit plans, net (1.0 ) 0.3 (0.7 ) Currency translation adjustments (9.7 ) — (9.7 ) Gain (loss) from hedging activities 0.7 (0.2 ) 0.5 Other comprehensive income (loss) attributable to W. R. Grace & Co. shareholders $ (10.0 ) $ 0.1 $ (9.9 ) Three Months Ended June 30, 2016 Pre-Tax Amount Tax Benefit/ (Expense) After-Tax Amount Defined benefit pension and other postretirement plans: Amortization of net prior service credit included in net periodic benefit cost $ (0.6 ) $ 0.2 $ (0.4 ) Amortization of net deferred actuarial loss included in net periodic benefit cost 0.1 (0.1 ) — Benefit plans, net (0.5 ) 0.1 (0.4 ) Currency translation adjustments 1.3 — 1.3 Gain (loss) from hedging activities (0.4 ) 0.1 (0.3 ) Other comprehensive income (loss) attributable to W. R. Grace & Co. shareholders $ 0.4 $ 0.2 $ 0.6 Six Months Ended June 30, 2016 Pre-Tax Amount Tax Benefit/ (Expense) After-Tax Amount Defined benefit pension and other postretirement plans: Amortization of net prior service credit included in net periodic benefit cost $ (1.3 ) $ 0.5 $ (0.8 ) Amortization of net deferred actuarial loss included in net periodic benefit cost 0.3 (0.2 ) 0.1 Benefit plans, net (1.0 ) 0.3 (0.7 ) Currency translation adjustments (4.1 ) — (4.1 ) Gain (loss) from hedging activities (5.1 ) 1.8 (3.3 ) Other comprehensive income (loss) attributable to W. R. Grace & Co. shareholders $ (10.2 ) $ 2.1 $ (8.1 )
Schedule of components of accumulated other comprehensive loss	The following tables present the changes in accumulated other comprehensive income (loss), net of tax, for the six months ended June 30, 2017 and 2016 : Six Months Ended June 30, 2017 Defined Benefit Pension and Other Postretirement Plans Currency Translation Adjustments Gain (Loss) from Hedging Activities Total Beginning balance $ 2.2 $ 67.6 $ (3.4 ) $ 66.4 Other comprehensive income (loss) before reclassifications — (9.7 ) (0.7 ) (10.4 ) Amounts reclassified from accumulated other comprehensive income (loss) (0.7 ) — 1.2 0.5 Net current-period other comprehensive income (loss) (0.7 ) (9.7 ) 0.5 (9.9 ) Ending balance $ 1.5 $ 57.9 $ (2.9 ) $ 56.5 Six Months Ended June 30, 2016 Defined Benefit Pension and Other Postretirement Plans Currency Translation Adjustments Gain (Loss) from Hedging Activities Total Beginning balance $ 3.0 $ (66.1 ) $ (3.7 ) $ (66.8 ) Other comprehensive income (loss) before reclassifications — (4.1 ) (4.4 ) (8.5 ) Amounts reclassified from accumulated other comprehensive income (loss) (0.7 ) — 1.1 0.4 Net current-period other comprehensive income (loss) (0.7 ) (4.1 ) (3.3 ) (8.1 ) Distribution of GCP (0.2 ) 135.5 — 135.3 Ending balance $ 2.1 $ 65.3 $ (7.0 ) $ 60.4

Earnings Per Share (Tables)

Earnings Per Share (Tables)	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Schedule of reconciliation of the numerators and denominators used in calculating basic and diluted earnings per share	The following table shows a reconciliation of the numerators and denominators used in calculating basic and diluted earnings per share. Three Months Ended June 30, Six Months Ended June 30, (In millions, except per share amounts) 2017 2016 2017 2016 Numerators Income (loss) from continuing operations attributable to W. R. Grace & Co. shareholders $ 43.9 $ 38.1 $ 86.8 $ 48.5 Income (loss) from discontinued operations, net of income taxes — 0.6 — (9.3 ) Net income (loss) attributable to W. R. Grace & Co. shareholders $ 43.9 $ 38.7 $ 86.8 $ 39.2 Denominators Weighted average common shares—basic calculation 68.3 70.5 68.3 70.5 Dilutive effect of employee stock options 0.1 0.4 0.2 0.5 Weighted average common shares—diluted calculation 68.4 70.9 68.5 71.0 Basic earnings per share attributable to W. R. Grace & Co. shareholders Income (loss) from continuing operations $ 0.64 $ 0.54 $ 1.27 $ 0.69 Income (loss) from discontinued operations, net of income taxes — 0.01 — (0.13 ) Net income (loss) $ 0.64 $ 0.55 $ 1.27 $ 0.56 Diluted earnings per share attributable to W. R. Grace & Co. shareholders Income (loss) from continuing operations $ 0.64 $ 0.54 $ 1.27 $ 0.68 Income (loss) from discontinued operations, net of income taxes — 0.01 — (0.13 ) Net income (loss) $ 0.64 $ 0.55 $ 1.27 $ 0.55

Operating Segment Information (

Operating Segment Information (Tables)	6 Months Ended
	Jun. 30, 2017
Segment Reporting [Abstract]
Schedule of operating segment data	Reportable Segment Data Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Net Sales Catalysts Technologies $ 320.5 $ 278.4 $ 614.3 $ 539.0 Materials Technologies 109.0 112.1 213.2 214.3 Total $ 429.5 $ 390.5 $ 827.5 $ 753.3 Adjusted EBIT Catalysts Technologies segment operating income $ 101.3 $ 87.5 $ 182.5 $ 165.8 Materials Technologies segment operating income 24.2 28.0 49.0 48.6 Corporate costs (18.3 ) (16.3 ) (34.4 ) (29.5 ) Certain pension costs (3.2 ) (3.1 ) (6.3 ) (6.2 ) Total $ 104.0 $ 96.1 $ 190.8 $ 178.7
Schedule of reconciliation of operating segment data to financial statements	Grace Adjusted EBIT for the three and six months ended June 30, 2017 and 2016 , is reconciled below to income from continuing operations before income taxes presented in the accompanying Consolidated Statements of Operations. Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Grace Adjusted EBIT $ 104.0 $ 96.1 $ 190.8 $ 178.7 (Costs) benefit related to legacy product, environmental and other claims (14.9 ) (6.7 ) (17.0 ) (11.1 ) Restructuring and repositioning expenses (5.4 ) (9.4 ) (7.7 ) (23.0 ) Pension MTM adjustment and other related costs, net — 0.7 (1.9 ) 0.9 Income and expense items related to divested businesses (0.7 ) 0.1 (1.0 ) (0.2 ) Third-party acquisition-related costs — (2.5 ) — (2.5 ) Gain on sale of product line — 0.7 — 0.7 Loss on early extinguishment of debt — — — (11.1 ) Interest expense, net (19.5 ) (19.4 ) (38.8 ) (41.2 ) Net income (loss) attributable to noncontrolling interests (0.4 ) (0.2 ) (0.4 ) (0.4 ) Income from continuing operations before income taxes $ 63.1 $ 59.4 $ 124.0 $ 90.8
Schedule of geographic area data	The table below presents information related to the geographic areas in which Grace operates. Sales are attributed to geographic areas based on customer location. Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Net Sales United States $ 108.8 $ 112.4 $ 212.6 $ 220.6 Canada and Puerto Rico 12.0 11.6 23.9 22.3 Total North America 120.8 124.0 236.5 242.9 Europe Middle East Africa 163.9 158.4 312.6 300.8 Asia Pacific 115.5 83.1 215.4 155.2 Latin America 29.3 25.0 63.0 54.4 Total $ 429.5 $ 390.5 $ 827.5 $ 753.3

Unconsolidated Affiliate (Table

Unconsolidated Affiliate (Tables)	6 Months Ended
	Jun. 30, 2017
Equity Method Investments and Joint Ventures [Abstract]
Summary of financial information of equity method investee	The following summary presents ART's assets, liabilities and results of operations. (In millions) June 30, December 31, 2016 Summary Balance Sheet information: Current assets $ 246.7 $ 249.2 Noncurrent assets 84.9 84.8 Total assets $ 331.6 $ 334.0 Current liabilities $ 71.7 $ 102.0 Noncurrent liabilities — 0.3 Total liabilities $ 71.7 $ 102.3 Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Net sales $ 110.5 $ 81.7 $ 207.9 $ 145.7 Costs and expenses applicable to net sales 94.7 75.2 173.6 123.4 Income before income taxes 12.6 5.3 26.8 19.2 Net income 12.2 5.1 26.2 18.9
Schedule of financial data related to transactions between Grace and ART	The table below presents summary financial data related to transactions between Grace and ART. Three Months Ended June 30, Six Months Ended June 30, (In millions) 2017 2016 2017 2016 Grace sales of catalysts to ART $ 53.1 $ 43.8 $ 104.5 $ 100.3 Mark-up on Grace's sales to ART included as a reduction of Grace's cost of goods sold 1.0 1.1 2.0 2.0 Charges for fixed costs, research and development, selling, general and administrative services, and depreciation to ART 10.4 6.1 20.8 12.3 The table below lists Grace balances related to ART. (in millions) June 30, December 31, Accounts receivable $ 3.3 $ 14.9 Noncurrent asset 27.4 27.0 Accounts payable 28.8 28.7 Debt payable within one year 7.8 7.6 Debt payable after one year 32.2 31.9 Noncurrent liability 27.4 27.0

Discontinued Operations (Tables

Discontinued Operations (Tables)	6 Months Ended
	Jun. 30, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Groups, Including Discontinued Operations	GCP's historical financial results through the February 3, 2016, Distribution Date and other effects of the Separation for the six months ended June 30, 2016, are presented as discontinued operations as summarized below: Six Months Ended June 30, (In millions) 2016 Net sales $ 99.6 Cost of goods sold 62.6 Gross profit 37.0 Selling, general and administrative expenses 21.6 Research and development expenses 1.7 Repositioning expenses 22.0 Interest expense and related financing costs 0.7 Other expense, net 3.9 Total costs and expenses 49.9 (Loss) Income from discontinued operations before income taxes (12.9 ) Benefit from (provision for) income taxes 3.7 (Loss) Income from discontinued operations after income taxes (9.2 ) Less: Net income attributable to noncontrolling interests (0.1 ) Net (loss) income from discontinued operations $ (9.3 )

Basis of Presentation and Sum37

Basis of Presentation and Summary of Significant Accounting and Financial Reporting Policies (Details)	3 Months Ended	6 Months Ended
	Mar. 31, 2016shares	Jun. 30, 2017segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of Reportable Segments | segment		2
Number of shares distributed per each share held at close (in shares) | shares	1

Basis of Presentation and Sum38

Basis of Presentation and Summary of Significant Accounting and Financial Reporting Policies Recently Adopted Accounting Standards (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted cash and cash equivalents	$ 10.8	$ 10

Inventories (Details)

Inventories (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Raw materials	$ 55.3	$ 57.7
In process	36	33.4
Finished products	123.1	115.8
Other	22.1	21.1
Total inventories	$ 236.5	$ 228

Debt - Components of Debt (Deta

Debt - Components of Debt (Details) - USD ($) $ in Millions		Jun. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Debt payable—unconsolidated affiliate		$ 40	$ 39.5
Deferred payment obligation		0	30
Total debt		1,603	1,584.1
Debt payable within one year		86.5	76.5
Debt payable after one year		$ 1,516.5	$ 1,507.6
Weighted average interest rates on total debt		4.60%	4.60%
5.125% Senior Notes, Due 2021
Debt Instrument [Line Items]
Interest rate (percent)		5.125%	5.125%
Unamortized discount and debt issuance costs		$ 6.6	$ 7.3
Total debt		693.4	692.7
Term Loan B (USD)
Debt Instrument [Line Items]
Unamortized discount and debt issuance costs		5.1	5.7
Total debt		$ 403.3	$ 402.7
5.625% Senior Notes, Due 2024
Debt Instrument [Line Items]
Interest rate (percent)		5.625%	5.625%
Unamortized discount and debt issuance costs		$ 3.7	$ 4
Total debt		296.3	296
Term Loan B (EUR)
Debt Instrument [Line Items]
Unamortized discount and debt issuance costs		1.1	1.3
Total debt		89.9	82.5
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term Line of Credit		40	0
Other borrowings
Debt Instrument [Line Items]
Total debt	[1]	$ 40.1	$ 40.7
[1]	(1) Represents borrowings under various lines of credit and other borrowings, primarily by non-U.S. subsidiaries.

Debt - Debt Maturity Schedule (

Debt - Debt Maturity Schedule (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Maturities of Long-term Debt [Abstract]
2,017	$ 82.4
2,018	8.4
2,019	7.8
2,020	6.6
2,021	1,191.7
Thereafter	306.1
Total debt	$ 1,603	$ 1,584.1

Debt - Narrative (Details)

Debt - Narrative (Details) € in Millions	Jan. 27, 2016USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016EUR (€)	Mar. 31, 2016USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Feb. 03, 2017USD ($)	Dec. 31, 2016USD ($)
Debt Instrument [Line Items]
ZAI P D Account, Payment on Third Anniversary of Effective Date of Joint Plan								$ 30,000,000
Distribution from GCP	$ 750,000,000					$ 0	$ 750,000,000
Proceeds from divestiture of business used to repay debt					$ 600,000,000
Repayments of debt						61,500,000	609,400,000
Loss on early extinguishment of debt		$ 0	$ 0			0	$ 11,100,000
Term Loan B (USD)
Debt Instrument [Line Items]
Repayments of debt					$ 526,900,000
Term Loan B (EUR)
Debt Instrument [Line Items]
Repayments of debt | €				€ 67.3
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility amount outstanding		40,000,000				40,000,000			$ 0
Maximum Borrowing Capacity		300,000,000				300,000,000
Line of Credit Facility, Current Borrowing Capacity		$ 222,300,000				$ 222,300,000

Fair Value Measurements and R43

Fair Value Measurements and Risk - Carrying Amounts and Fair Values of Debt (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt		$ 1,603		$ 1,603		$ 1,584.1
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt		1,603		1,603		1,584.1
Other borrowings		120.1		120.1		110.2
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt		1,676.7		1,676.7		1,633.2
Other borrowings		120.1		120.1		110.2
Term Loan B (USD)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized discount and debt issuance costs		5.1		5.1		5.7
Term Loan B (USD) | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt	[1]	403.3		403.3		402.7
Term Loan B (USD) | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt		402.8		402.8		408.2
Term Loan B (EUR)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized discount and debt issuance costs		1.1		1.1		1.3
Term Loan B (EUR) | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt	[1]	89.9		89.9		82.5
Term Loan B (EUR) | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt		89.9		89.9		82
5.125% Senior Notes, Due 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized discount and debt issuance costs		6.6		6.6		7.3
Total debt		$ 693.4		$ 693.4		$ 692.7
Interest rate (percent)		5.125%		5.125%		5.125%
5.125% Senior Notes, Due 2021 | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt	[2]	$ 693.4		$ 693.4		$ 692.7
5.125% Senior Notes, Due 2021 | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt		745.4		745.4		721.3
5.625% Senior Notes, Due 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized discount and debt issuance costs		3.7		3.7		4
Total debt		$ 296.3		$ 296.3		$ 296
Interest rate (percent)		5.625%		5.625%		5.625%
5.625% Senior Notes, Due 2024 | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt	[2]	$ 296.3		$ 296.3		$ 296
5.625% Senior Notes, Due 2024 | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt		318.5		318.5		$ 311.5
Net Investment Hedging
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net		$ 0	$ 0	$ 0	$ 0
[1]	(2)Carrying amounts are net of unamortized debt issuance costs and discounts of $5.1 million and $1.1 million as of June 30, 2017, and $5.7 million and $1.3 million as of December 31, 2016, related to the U.S. dollar term loan and euro term loan, respectively.
[2]	(1)Carrying amounts are net of unamortized debt issuance costs of $6.6 million and $3.7 million as of June 30, 2017, and $7.3 million and $4.0 million as of December 31, 2016, related to the 5.125% senior notes due 2021 and 5.625% senior notes due 2024, respectively.

Fair Value Measurements and R44

Fair Value Measurements and Risk - Narrative (Details) € in Millions	Jun. 30, 2017EUR (€)Currencycountry	Feb. 03, 2015USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of countries in which entity operates | country	60
Number of currencies used | Currency	30
Deferred intercompany royalties designated as hedging instrument	€ 45
Term Loan B (EUR)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Term loan principal designated as hedging instrument	80.1
Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total contract value | $		$ 250,000,000
Fixed interest rate (percent)		2.393%
Currency Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cross-currency swaps	€ 170

Fair Value Measurements and R45

Fair Value Measurements and Risk - Financial Asset and Liabilities (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Assets
Currency derivatives	$ 3.6	$ 8.8
Total Assets	3.6	8.8
Liabilities
Interest rate derivatives	5.1	6
Currency derivatives	11.6	0.9
Total Liabilities	16.7	6.9
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1)
Assets
Currency derivatives	0	0
Total Assets	0	0
Liabilities
Interest rate derivatives	0	0
Currency derivatives	0	0
Total Liabilities	0	0
Significant Other Observable Inputs (Level 2)
Assets
Currency derivatives	3.6	8.8
Total Assets	3.6	8.8
Liabilities
Interest rate derivatives	5.1	6
Currency derivatives	11.6	0.9
Total Liabilities	16.7	6.9
Significant Unobservable Inputs (Level 3)
Assets
Currency derivatives	0	0
Total Assets	0	0
Liabilities
Interest rate derivatives	0	0
Currency derivatives	0	0
Total Liabilities	$ 0	$ 0

Fair Value Measurements and R46

Fair Value Measurements and Risk - Derivative Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Asset Derivatives
Total derivatives	$ 3.6	$ 8.8
Liability Derivatives
Total derivatives	16.7	6.9
Designated as Hedging Instrument | Other current assets
Asset Derivatives
Currency contracts	3	4
Interest rate contracts	0	0
Designated as Hedging Instrument | Other assets
Asset Derivatives
Currency contracts	0	4
Interest rate contracts	0	0
Designated as Hedging Instrument | Other current liabilities
Liability Derivatives
Currency contracts	0.4	0
Interest rate derivatives	1.9	2.8
Designated as Hedging Instrument | Other liabilities
Liability Derivatives
Currency contracts	10.5	0
Interest rate derivatives	3.2	3.2
Not Designated as Hedging Instrument | Other current assets
Asset Derivatives
Currency contracts	0.6	0.8
Not Designated as Hedging Instrument | Other current liabilities
Liability Derivatives
Currency contracts	$ 0.7	$ 0.9

Fair Value Measurements and R47

Fair Value Measurements and Risk - Gain (Loss) on Derivative Instruments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Cross-currency swap [Member]
Gains and losses on derivative instruments
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	$ (6.1)	$ 0.1	$ (8.6)	$ 0.1
Cash Flow Hedging
Gains and losses on derivative instruments
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	(1.1)	(1.7)	(1.1)	(6.3)
Amount of Gain (Loss) Reclassified from OCI into Income (Effective Portion)	0.9	1.2	1.8	1.7
Cash Flow Hedging | Interest rate contracts | Interest expense
Gains and losses on derivative instruments
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	(1.1)	(1.9)	(1)	(6.4)
Amount of Gain (Loss) Reclassified from OCI into Income (Effective Portion)	0.8	1.1	1.7	2.1
Cash Flow Hedging | Currency contracts | Other expense
Gains and losses on derivative instruments
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	0	0.2	(0.1)	0.1
Amount of Gain (Loss) Reclassified from OCI into Income (Effective Portion)	$ 0.1	$ 0.1	$ 0.1	$ (0.4)

Fair Value Measurements and R48

Fair Value Measurements and Risk - Gain (Loss) on Nonderivative Instrument (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Cross-currency swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	$ (6.1)	$ 0.1	$ (8.6)	$ 0.1
Foreign currency denominated debt [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI in Currency Translation Adjustments (Effective Portion)	(4.9)		(7.2)
Foreign currency denominated deferred intercompany royalties [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI in Currency Translation Adjustments (Effective Portion)	(2.9)		(4.4)
Net Investment Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	0	0	0	0
Amount of Gain (Loss) Recognized in OCI in Currency Translation Adjustments (Effective Portion)	$ (7.8)	$ 0.9	$ (11.6)	$ (0.5)

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Tax Credit Carryforward [Line Items]
Effective tax rate (percent)	32.10%	35.60%
Effective income tax rate reconciliation, stock option exercises, amount	$ 3	$ 6.7
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	$ 1.1
Change in deferred tax assets valuation allowance		$ 10.1
Period allowed for carryforward of operation loss	20 years
Income tax deductions generated from deferred payment obligation	$ 30
Deferred Tax Assets, Net [Abstract]
Deferred Tax Asset (Net of Liabilities)	728.7
Valuation Allowance	(31.4)
Net Deferred Tax Asset	697.3
Taxable income required to realized DTA total amount	1,700
Taxable income required to realize DTA per year	95
United States - Federal
Deferred Tax Assets, Net [Abstract]
Deferred Tax Asset (Net of Liabilities)	627.1
Valuation Allowance	(17.7)
Net Deferred Tax Asset	609.4
United States - States
Deferred Tax Assets, Net [Abstract]
Deferred Tax Asset (Net of Liabilities)	50.9
Valuation Allowance	(11.2)
Net Deferred Tax Asset	39.7
Germany
Deferred Tax Assets, Net [Abstract]
Deferred Tax Asset (Net of Liabilities)	42.7
Valuation Allowance	0
Net Deferred Tax Asset	42.7
Other foreign
Deferred Tax Assets, Net [Abstract]
Deferred Tax Asset (Net of Liabilities)	8
Valuation Allowance	(2.5)
Net Deferred Tax Asset	$ 5.5

Pension Plans and Other Postr50

Pension Plans and Other Postretirement Benefit Plans - Pension Plans and Other Postretirement Benefit (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Funded status of fully funded, underfunded, and unfunded pension plans:
Underfunded and unfunded defined benefit pension plans	$ 444.2	$ 424.3
Pension liabilities included in other current liabilities	15	14.4
Net funded status	(459.2)	(438.7)
Underfunded defined benefit pension plans [Member]
Funded status of fully funded, underfunded, and unfunded pension plans:
Underfunded and unfunded defined benefit pension plans	81.5	83.1
Unfunded defined benefit pension plans [Member]
Funded status of fully funded, underfunded, and unfunded pension plans:
Underfunded and unfunded defined benefit pension plans	$ 362.7	$ 341.2

Pension Plans and Other Postr51

Pension Plans and Other Postretirement Benefit Plans - Components of Net Periodic Benefit Cost (Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Net Periodic Benefit Cost
Pension MTM adjustment and other related costs, net	$ 0	$ (0.7)	$ 1.9	$ (0.9)
Defined contribution retirement plan
Percentage that the employer contributes of employee contributions under 401(k) plan			100.00%
Maximum percentage of employee compensation match by employer to defined contribution plan			6.00%
Costs related to defined contribution retirement plan	3	2.7	$ 5.7	5.4
U.S. Pension Plans
Net Periodic Benefit Cost
Service cost	4.3	4.4	8.6	9.4
Interest cost	10.5	10.2	21	20.7
Expected return on plan assets	(14.4)	(14.2)	(28.8)	(28.8)
Amortization of prior service credit	(0.1)	0	(0.2)	(0.1)
Amortization of net deferred actuarial loss	0	0	0	0
Curtailment gain	0	0	0	0
Net periodic benefit cost (income)			0.6	1.2
Less: discontinued operations			0	(0.5)
Net periodic benefit cost (income) from continuing operations	0.3	0.4	0.6	0.7
Non-U.S. Pension Plans
Net Periodic Benefit Cost
Service cost	2	1.7	4	3.7
Interest cost	1.1	1.3	2.1	3.3
Expected return on plan assets	(0.2)	(0.3)	(0.4)	(1.3)
Amortization of prior service credit	0	0	0	0
Amortization of net deferred actuarial loss	0	0	0	0
Curtailment gain	0	(0.7)	0	(0.7)
Net periodic benefit cost (income)			5.7	5
Less: discontinued operations			0	(0.2)
Net periodic benefit cost (income) from continuing operations	2.9	2	5.7	4.8
Other Postretirement
Net Periodic Benefit Cost
Service cost	0	0	0	0
Interest cost	0	0	0	0
Expected return on plan assets	0	0	0	0
Amortization of prior service credit	(0.5)	(0.6)	(1)	(1.2)
Amortization of net deferred actuarial loss	0.1	0.1	0.2	0.3
Curtailment gain	0	0	0	0
Net periodic benefit cost (income)			(0.8)	(0.9)
Less: discontinued operations			0	0
Net periodic benefit cost (income) from continuing operations	$ (0.4)	$ (0.5)	$ (0.8)	$ (0.9)

Other Balance Sheet Accounts (D

Other Balance Sheet Accounts (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Other Current Liabilities
Environmental contingencies	$ 26.8	$ 32.5
Deferred revenue	21.2	27.2
Accrued compensation	39	49.6
Accrued interest	17	16.2
Pension liabilities included in other current liabilities	15	14.4
Income taxes payable	8.5	5.7
Other accrued liabilities	56.1	63.3
Total Other Current Liabilities	183.6	208.9
Other Liabilities, Noncurrent [Abstract]
Environmental contingencies	41.5	33.8
Liability to unconsolidated affiliate	27.4	27
Asset Retirement Obligation	8.7	10.2
Postemployment liability	7	7.2
Deferred revenue	9.4	2.3
Other noncurrent liabilities	59.6	46.2
Other Liabilities, Noncurrent	$ 153.6	$ 126.7

Commitments and Contingent Li53

Commitments and Contingent Liabilities - Asbestos-Related Liabilities (Details) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2017USD ($)shares	Jun. 30, 2017USD ($)paymentshares	Feb. 03, 2017USD ($)	Dec. 31, 2016USD ($)	Feb. 03, 2014USD ($)
Other Commitments Chapter 11 [Abstract]
ZAI PD account funding					$ 34.4
ZAI P D Account, Payment on Third Anniversary of Effective Date of Joint Plan			$ 30
ZAI P D account, maximum number of contingent deferred payments | payment		10
ZAI P D account, deferred payments, each year for twenty years		$ 8
Period in which ZAI PD contingent deferred payments will be made		20 years
Minimum ZAI P D account assets for condition in relation to contingent obligation payments	$ 10	$ 10
Frequency of PD trust payments		6 months
Number of shares issuable under warrant (in shares) | shares	77,372,257	77,372,257
Environmental remediation
Estimated liability for environmental investigative and remediation costs	$ 68.3	$ 68.3		$ 66.3
Vermiculite Related Matters [Member]
Environmental remediation
Accrual for Environmental Investigative and Remediation Costs, Period Increase (Decrease)	4.3
Estimated liability for environmental investigative and remediation costs	26.8	26.8		31.2
Non-Vermiculite Related Matters [Member]
Environmental remediation
Accrual for Environmental Investigative and Remediation Costs, Period Increase (Decrease)	8.9
Estimated liability for environmental investigative and remediation costs	41.5	$ 41.5		$ 35.1
Non-Vermiculite Related Remediation [Member]
Environmental remediation
Accrual for Environmental Investigative and Remediation Costs, Period Increase (Decrease)	$ 7.2

Commitments and Contingent Li54

Commitments and Contingent Liabilities - Financial Assurances (Details) $ in Millions	Jun. 30, 2017USD ($)
Financial Guarantee
Financial assurances
Gross financial assurances issued and outstanding	$ 122.9
Surety Bonds [Member]
Financial assurances
Gross financial assurances issued and outstanding	39.5
Standby Letters of Credit [Member]
Financial assurances
Gross financial assurances issued and outstanding	$ 83.4

Restructuring Expenses and Re55

Restructuring Expenses and Repositioning Expenses - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Restructuring and Related Activities [Abstract]
Repositioning expenses	$ 3.3	$ 1.5	$ 2.8	$ 6.6

Restructuring Expenses and Re56

Restructuring Expenses and Repositioning Expenses - Expenses and Asset Impairments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	$ 2	$ 7.9	$ 4.8	$ 16.4
Grace Catalysts Technologies [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	0	0.6	0.4	1.1
Grace Materials Technologies [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	0.1	7.3	0.3	15.2
Corporate, Non-Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	$ 1.9	$ 0	$ 4.1	$ 0.1

Restructuring Expenses and Re57

Restructuring Expenses and Repositioning Expenses - Liability Rollforward (Details) $ in Millions	6 Months Ended
	Jun. 30, 2017USD ($)
Restructuring Reserve [Roll Forward]
Balance, December 31, 2016	$ 9.6
Accruals for severance and other costs	4.4
Payments	(7.2)
Currency translation adjustments and other	0.1
Balance, June 30, 2017	$ 6.9

Other Expense (Income), net (De

Other Expense (Income), net (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Other Income and Expenses [Abstract]
Business interruption insurance recovery	$ (10.6)	$ 0	$ (13.1)	$ 0
Third-party acquisition-related costs	0	2.5	0	2.5
Chapter 11 expenses, net	0.6	0.8	1.5	2
Currency transaction effects	1.5	(0.2)	2	0.3
Net (gain) loss on sales of investments and disposals of assets	0.4	(0.3)	0.8	0.2
Interest income	(0.6)	(0.4)	(0.8)	(0.6)
Loss on early extinguishment of debt	0	0	0	11.1
Other miscellaneous (income) expense	(0.9)	0.7	(2.2)	(1.7)
Total other (income) expense, net	$ (9.6)	$ 3.1	$ (11.8)	$ 13.8

Other Expense (Income), net Oth

Other Expense (Income), net Other Expense (Income), net - Business Interruption Insurance Recovery (Details)	6 Months Ended
	Jun. 30, 2017USD ($)
Business Interruption Loss [Line Items]
Business Interruption Insurance Policy Limit	$ 25,000,000
Proceeds from business interruption insurance recovery	$ 10,400,000

Other Comprehensive Loss - OCI

Other Comprehensive Loss - OCI Components (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-Tax Amount	$ (0.6)	$ (0.6)	$ (1.2)	$ (1.3)
Tax Benefit/ (Expense)	0.2	0.2	0.4	0.5
After-Tax Amount	(0.4)	(0.4)	(0.8)	(0.8)
Defined Benefit Pension and Other Postretirement Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-Tax Amount	0.1	0.1	0.2	0.3
Tax Benefit/ (Expense)	(0.1)	(0.1)	(0.1)	(0.2)
After-Tax Amount	0	0	0.1	0.1
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-Tax Amount	(0.5)	(0.5)	(1)	(1)
Tax Benefit/ (Expense)	0.1	0.1	0.3	0.3
After-Tax Amount	(0.4)	(0.4)	(0.7)	(0.7)
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-Tax Amount	(8.3)	1.3	(9.7)	(4.1)
Tax Benefit/ (Expense)	0	0	0	0
After-Tax Amount	(8.3)	1.3	(9.7)	(4.1)
Gain (Loss) from Hedging Activities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-Tax Amount	(0.2)	(0.4)	0.7	(5.1)
Tax Benefit/ (Expense)	0	0.1	(0.2)	1.8
After-Tax Amount	(0.2)	(0.3)	0.5	(3.3)
AOCI Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-Tax Amount	(9)	0.4	(10)	(10.2)
Tax Benefit/ (Expense)	0.1	0.2	0.1	2.1
After-Tax Amount	$ (8.9)	$ 0.6	$ (9.9)	$ (8.1)

Other Comprehensive Loss - AOCI

Other Comprehensive Loss - AOCI (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			$ 372.4	$ 212.5
Total other comprehensive income (loss)	$ (8.9)	$ 0.6	(9.9)	(5.5)
Ending balance	405.6	489	405.6	489
Defined Benefit Pension and Other Postretirement Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			2.2	3
Other comprehensive income (loss) before reclassifications			0	0
Amounts reclassified from accumulated other comprehensive income (loss)			(0.7)	(0.7)
Total other comprehensive income (loss)			(0.7)	(0.7)
Distribution of GCP				(0.2)
Ending balance	1.5	2.1	1.5	2.1
Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			67.6	(66.1)
Other comprehensive income (loss) before reclassifications			(9.7)	(4.1)
Amounts reclassified from accumulated other comprehensive income (loss)			0	0
Total other comprehensive income (loss)			(9.7)	(4.1)
Distribution of GCP				135.5
Ending balance	57.9	65.3	57.9	65.3
Gain (Loss) from Hedging Activities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(3.4)	(3.7)
Other comprehensive income (loss) before reclassifications			(0.7)	(4.4)
Amounts reclassified from accumulated other comprehensive income (loss)			1.2	1.1
Total other comprehensive income (loss)			0.5	(3.3)
Distribution of GCP				0
Ending balance	(2.9)	(7)	(2.9)	(7)
AOCI Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			66.4	(66.8)
Other comprehensive income (loss) before reclassifications			(10.4)	(8.5)
Amounts reclassified from accumulated other comprehensive income (loss)			0.5	0.4
Total other comprehensive income (loss)			(9.9)	(8.1)
Distribution of GCP				135.3
Ending balance	$ 56.5	$ 60.4	$ 56.5	$ 60.4

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Feb. 08, 2017	Feb. 05, 2015
Numerators
Income (loss) from continuing operations attributable to W. R. Grace & Co. shareholders	$ 43,900,000	$ 38,100,000	$ 86,800,000	$ 48,500,000
Income (loss) from discontinued operations, net of income taxes	0	600,000	0	(9,300,000)
Net income (loss) attributable to W. R. Grace & Co. shareholders	$ 43,900,000	$ 38,700,000	$ 86,800,000	$ 39,200,000
Denominators
Weighted average common shares—basic calculation (in shares)	68,300,000	70,500,000	68,300,000	70,500,000
Dilutive effect of employee stock options (in shares)	100,000	400,000	200,000	500,000
Weighted average common shares—diluted calculation (in shares)	68,400,000	70,900,000	68,500,000	71,000,000
Basic earnings per share attributable to W. R. Grace & Co. shareholders
Net income from continuing operations attributable to W. R. Grace & Co. shareholders (in USD per share)	$ 0.64	$ 0.54	$ 1.27	$ 0.69
(Loss) income from discontinued operations (in USD per share)	0	0.01	0	(0.13)
Net income (loss)	0.64	0.55	1.27	0.56
Diluted earnings per share attributable to W. R. Grace & Co. shareholders
Income (Loss) from Continuing Operations, Per Diluted Share	0.64	0.54	1.27	0.68
Income (loss) from discontinued operations, net of income taxes	0	0.01	0	(0.13)
Net income (loss)	$ 0.64	$ 0.55	$ 1.27	$ 0.55
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock Repurchase Program, Authorized Amount					$ 250,000,000	$ 500,000,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 3,900,000		$ 3,900,000
Stock repurchased during period (in shares)			425,673	472,400
Cash paid for repurchases of common stock			$ 30,000,000	$ 35,100,000
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive options outstanding	1,600,000	1,000,000	1,500,000	1,200,000
Minimum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock Repurchase Program, Period in Force			24 months
Maximum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock Repurchase Program, Period in Force			36 months

Operating Segment Information -

Operating Segment Information - Reportable Segment Data (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Jun. 30, 2017USD ($)segment	Jun. 30, 2016USD ($)	Dec. 31, 2016USD ($)
Operating segment information
Number of Reportable Segments | segment			2
Number of operating segments | segment			2
Net Sales
Net sales	$ 429.5	$ 390.5	$ 827.5	$ 753.3
Adjusted EBIT
Total	104	96.1	190.8	178.7
Total Assets
Assets	2,989.9		2,989.9		$ 2,911.8
Reconciliation of operating segment data to financial statements
(Costs) benefit related to legacy product, environmental and other claims	14.9	6.7	17	11.1
Restructuring and repositioning expenses	5.4	9.4	7.7	23
Pension MTM adjustment and other related costs, net	0	(0.7)	1.9	(0.9)
Income and expense items related to divested businesses	0.7	(0.1)	1	0.2
Third-party acquisition-related costs	0	2.5	0	2.5
Gain on sale of product line	0	0.7	0	0.7
Loss on early extinguishment of debt	0	0	0	(11.1)
Interest expense, net	(19.5)	(19.4)	(38.8)	(41.2)
Net income (loss) attributable to noncontrolling interests	0.4	0.2	0.4	0.4
Income (loss) from continuing operations before income taxes	63.1	59.4	$ 124	90.8
Grace Catalysts Technologies [Member]
Operating segment information
Number of Reportable Segments | segment			1
Adjusted EBIT
Operating income	101.3	87.5	$ 182.5	165.8
Grace Materials Technologies [Member]
Adjusted EBIT
Operating income	24.2	28	49	48.6
Corporate, Non-Segment [Member]
Adjusted EBIT
Operating income			(34.4)	(29.5)
Certain pension costs	(3.2)	(3.1)	(6.3)	(6.2)
Operating Segments | Grace Catalysts Technologies [Member]
Net Sales
Net sales	320.5	278.4	614.3	539
Operating Segments | Grace Materials Technologies [Member]
Net Sales
Net sales	109	112.1	$ 213.2	$ 214.3
Corporate, Non-Segment [Member]
Adjusted EBIT
Operating income	$ (18.3)	$ (16.3)

Operating Segment Information64

Operating Segment Information - Geographic Area Data (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Geographic Area Data
Net sales	$ 429.5	$ 390.5	$ 827.5	$ 753.3
United States
Geographic Area Data
Net sales	108.8	112.4	212.6	220.6
Canada and Puerto Rico
Geographic Area Data
Net sales	12	11.6	23.9	22.3
Total North America
Geographic Area Data
Net sales	120.8	124	236.5	242.9
Europe Middle East Africa
Geographic Area Data
Net sales	163.9	158.4	312.6	300.8
Asia Pacific
Geographic Area Data
Net sales	115.5	83.1	215.4	155.2
Latin America
Geographic Area Data
Net sales	$ 29.3	$ 25	$ 63	$ 54.4

Unconsolidated Affiliate (Detai

Unconsolidated Affiliate (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Equity method investment ownership interest (percent)	50.00%		50.00%
Investment in unconsolidated affiliate	$ 131,900,000		$ 131,900,000		$ 117,600,000
Equity in earnings of unconsolidated affiliate	6,100,000	$ 2,600,000	13,100,000	$ 9,500,000
ART's assets, liabilities and results of operations
Current assets	246,700,000		246,700,000		249,200,000
Noncurrent assets	84,900,000		84,900,000		84,800,000
Total assets	331,600,000		331,600,000		334,000,000
Current liabilities	71,700,000		71,700,000		102,000,000
Noncurrent liabilities					300,000
Total liabilities	71,700,000		71,700,000		102,300,000
Net sales	110,500,000	81,700,000	207,900,000	145,700,000
Costs and expenses applicable to net sales	94,700,000	75,200,000	173,600,000	123,400,000
Income before income taxes	12,600,000	5,300,000	26,800,000	19,200,000
Net income	12,200,000	5,100,000	26,200,000	18,900,000
Related Party Transactions [Abstract]
Grace sales of catalysts to ART	53,100,000	43,800,000	104,500,000	100,300,000
Mark-up on Grace's sales to ART included as a reduction of Grace's cost of goods sold	1,000,000	1,100,000	2,000,000	2,000,000
Charges for fixed costs, research and development, selling, general and administrative services, and depreciation to ART	10,400,000	$ 6,100,000	20,800,000	$ 12,300,000
Investment in unconsolidated affiliates
Accounts receivable	3,300,000		3,300,000		14,900,000
Noncurrent asset	27,400,000		27,400,000		27,000,000
Accounts payable	28,800,000		28,800,000		28,700,000
Debt payable within one year	7,800,000		7,800,000		7,600,000
Debt payable after one year	32,200,000		32,200,000		31,900,000
Liability to unconsolidated affiliate	27,400,000		27,400,000		27,000,000
Grace
Investment in unconsolidated affiliates
Line of credit facility, maximum provided by Grace and Chevron each	15,000,000		$ 15,000,000
Commitment fee on credit facility (as a percent)			0.10%
Credit facility amount outstanding	0		$ 0		$ 0
Chevron
Investment in unconsolidated affiliates
Line of credit facility, maximum provided by Grace and Chevron each	$ 15,000,000		$ 15,000,000
Commitment fee on credit facility (as a percent)			0.10%

Discontinued Operations - Narra

Discontinued Operations - Narrative (Details) - USD ($)	Jan. 27, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Feb. 29, 2016	Jan. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Distribution from GCP	$ 750,000,000		$ 0	$ 750,000,000
Revolving Credit Facility
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Maximum Borrowing Capacity			$ 300,000,000
Line of Credit | Discontinued Operations, Disposed of by Sale | Grace Construction Products | GCP Credit Agreement | GCP Applied Technologies
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Issuance of Long-term Debt		$ 525,000,000
Distribution from GCP		250,000,000
Line of Credit | Discontinued Operations, Disposed of by Sale | Grace Construction Products | GCP Credit Agreement | Term Loan | GCP Applied Technologies
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Maximum Borrowing Capacity					$ 275,000,000
Line of Credit | Discontinued Operations, Disposed of by Sale | Grace Construction Products | GCP Credit Agreement | Revolving Credit Facility | GCP Applied Technologies
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Maximum Borrowing Capacity					$ 250,000,000
Senior Notes | Discontinued Operations, Disposed of by Sale | Grace Construction Products | 9.5% Senior Notes Due 2023 | GCP Applied Technologies
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Issuance of Long-term Debt		525,000,000
Interest rate (percent)						9.50%
Distribution from GCP		$ 500,000,000

Discontinued Operations Discont

Discontinued Operations Discontinued Operations - Statement of Operations (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales	$ 429.5	$ 390.5	$ 827.5	$ 753.3
Cost of goods sold	260.2	217.3	505	427.4
Gross profit	169.3	173.2	322.5	325.9
Selling, general and administrative expenses	70.3	66.4	136.8	134.4
Research and development expenses	12.9	12.4	26.1	24.1
Repositioning expenses	3.3	1.5	2.8	6.6
Interest expense and related financing costs	20.1	19.8	39.6	41.8
Other expense, net	(9.6)	3.1	(11.8)	13.8
Total costs and expenses	106.2	113.8	198.5	235.1
Net (loss) income from discontinued operations	$ 0	$ (0.6)	$ 0	9.3
Grace Construction Products | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales				99.6
Cost of goods sold				62.6
Gross profit				37
Selling, general and administrative expenses				21.6
Research and development expenses				1.7
Repositioning expenses				22
Interest expense and related financing costs				0.7
Other expense, net				3.9
Total costs and expenses				49.9
(Loss) Income from discontinued operations before income taxes				(12.9)
Benefit from (provision for) income taxes				3.7
(Loss) Income from discontinued operations after income taxes				(9.2)
Less: Net income attributable to noncontrolling interests				(0.1)
Net (loss) income from discontinued operations				$ 9.3

Acquisitions (Details)

Acquisitions (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill	$ 397.5	$ 394.2

Uncategorized Items - gra-20170

Label	Element	Value
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents	us-gaap_DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents	$ 143,400,000