GCP Applied (GCP) 10-Q 8 Nov 17 2017 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Oct. 31, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	GCP Applied Technologies Inc.
Entity Central Index Key	1,644,440
Document Type	10-Q
Document Period End Date	Sep. 30, 2017
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		71,636,080
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3

Consolidated Statements of Oper

Consolidated Statements of Operations (unaudited) - USD ($) shares in Millions, $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Statement [Abstract]
Net sales		$ 282.4	$ 263.4	$ 794.9	$ 785.1
Cost of goods sold		175.9	154.8	488.1	465.1
Gross profit		106.5	108.6	306.8	320
Selling, general and administrative expenses		76.3	67.4	221.9	199.5
Research and development expenses		5.2	4.7	15.2	13.6
Interest expense and related financing costs		21.6	18.8	56.1	49
Repositioning expenses		1.1	5.3	6.8	14.3
Restructuring expenses and asset impairments		2.1	0.4	13	1.4
Loss in Venezuela		36.7	0	38.3	0
Other income, net		(4)	(1.6)	(6.6)	(1.7)
Total costs and expenses		139	95	344.7	276.1
(Loss) income from continuing operations before income taxes		(32.5)	13.6	(37.9)	43.9
Income tax benefit (expense)		14.5	(2.5)	(3.7)	(9.8)
(Loss) income from continuing operations		(18)	11.1	(41.6)	34.1
Income from discontinued operations, net of income taxes		677.3	10.4	679.4	36.2
Net income		659.3	21.5	637.8	70.3
Less: Net income attributable to noncontrolling interests		(0.1)	(0.2)	(0.2)	(0.9)
Net income attributable to GCP shareholders		659.2	21.3	637.6	69.4
Amounts Attributable to GCP Shareholders:
(Loss) income from continuing operations attributable to GCP shareholders		(18.1)	10.9	(41.8)	33.2
Income from discontinued operations, net of income taxes		677.3	10.4	679.4	36.2
Net income attributable to GCP shareholders		$ 659.2	$ 21.3	$ 637.6	$ 69.4
Basic earnings per share:
Net (loss) income from continuing operations attributable to GCP shareholders (in usd per share)		$ (0.25)	$ 0.15	$ (0.59)	$ 0.47
Income from discontinued operations, net of income taxes (in usd per share)		9.46	0.15	9.54	0.51
Net income attributable to GCP shareholders (in usd per share)	[1]	$ 9.21	$ 0.30	$ 8.96	$ 0.98
Weighted average number of basic shares		71.6	71	71.2	70.8
Diluted earnings per share:
Net (loss) income from continuing operations attributable to GCP shareholders (in usd per share)	[2]	$ (0.25)	$ 0.15	$ (0.59)	$ 0.46
Income from discontinued operations, net of income taxes (in usd per share)	[2]	9.46	0.14	9.54	0.51
Net income attributable to GCP shareholders (in usd per share)	[1],[2]	$ 9.21	$ 0.30	$ 8.96	$ 0.97
Weighted average number of diluted shares		71.6	72.2	71.2	71.6
[1]	Amounts may not sum due to rounding
[2]	Dilutive effect only applicable to periods where there is net income from continuing operations.

Consolidated Balance Sheets (un

Consolidated Balance Sheets (unaudited) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Current Assets
Cash and cash equivalents	$ 771.4	$ 147
Trade accounts receivable, less allowance of $6.0 (2016—$4.5)	209.4	166.6
Inventories	108.4	89.3
Other current assets	59.2	42.9
Current assets held for sale	16.8	108
Total Current Assets	1,165.2	553.8
Properties and equipment, net	209.1	192.6
Goodwill	183.8	114.9
Technology and other intangible assets, net	76.9	52.6
Deferred income taxes	45.4	76.9
Overfunded defined benefit pension plans	22.1	21.2
Other assets	28.1	22.4
Noncurrent assets held for sale	2.5	55.4
Total Assets	1,733.1	1,089.8
Current Liabilities
Debt payable within one year	23.8	47.9
Accounts payable	120.8	95.9
Other current liabilities	310.3	119.5
Current liabilities held for sale	8.1	48.2
Total Current Liabilities	463	311.5
Debt payable after one year	520.3	783
Deferred income taxes	13.5	6.6
Unrecognized tax benefits	42.7	9.7
Underfunded and unfunded defined benefit pension plans	85.6	83.2
Other liabilities	35.5	13.9
Noncurrent liabilities held for sale	0.3	20.9
Total Liabilities	1,160.9	1,228.8
Commitments and Contingencies - Note 7
Stockholders' Equity (Deficit)
Common stock issued, par value $0.01; 300,000,000 shares authorized; outstanding: 71,628,903 and 71,081,764 respectively	0.7	0.7
Paid-in capital	25.1	11
Accumulated earnings (deficit)	632.9	(4.7)
Accumulated other comprehensive loss	(85)	(147.6)
Treasury stock	(3.1)	(2.1)
Total GCP Shareholders' Equity (Deficit)	570.6	(142.7)
Noncontrolling interests	1.6	3.7
Total Stockholders' Equity (Deficit)	572.2	(139)
Total Liabilities and Stockholders' Equity (Deficit)	$ 1,733.1	$ 1,089.8

Consolidated Balance Sheets (u4

Consolidated Balance Sheets (unaudited) (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Trade accounts receivable, allowance	$ 6	$ 4.5
Common stock issued, par value (in usd per share)	$ 0.01	$ 0.01
Common stock, number of shares authorized	300,000,000	300,000,000
Common stock, number of shares outstanding	71,628,903	71,081,764

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) (unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 659.3	$ 21.5	$ 637.8	$ 70.3
Other comprehensive income (loss):
Defined benefit pension and other postretirement plans, net of income taxes	(0.3)	0	(0.3)	(0.5)
Currency translation adjustments	46.2	3	63	3.5
Gain (loss) from hedging activities, net of income taxes	0.5	(0.1)	(0.1)	(0.1)
Total other comprehensive income attributable to noncontrolling interests	0	0	0	0.2
Total other comprehensive income	46.4	2.9	62.6	3.1
Comprehensive income	705.7	24.4	700.4	73.4
Less: Comprehensive income attributable to noncontrolling interests	(0.1)	(0.2)	(0.2)	(1.1)
Comprehensive income attributable to GCP shareholders	$ 705.6	$ 24.2	$ 700.2	$ 72.3

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (Deficit) (unaudited) - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Accumulated Earnings/(Deficit)	Net Parent Investment	Accumulated Other Comprehensive Loss	Noncontrolling Interests
Beginning balance at Dec. 31, 2015	$ 474.1	$ 0	$ 0	$ 0	$ 0	$ 598.3	$ (127.7)	$ 3.5
Beginning balance, shares at Dec. 31, 2015		0	0
Increase (Decrease) in Stockholders' Equity
Net income	70.3				62.2	7.2		0.9
Net transfer to parent	(672.2)					(672.2)
Issuance of common stock and reclassification of net parent investment in connection with Separation, shares		70.5
Issuance of common stock and reclassification of net parent investment in connection with Separation	0	$ 0.7			(67.4)	66.7
Issuance of common stock in connection with stock plans, shares		0.1
Share-based compensation	4.7				4.7
Exercise of stock options, shares		0.4
Exercise of stock options	4.1				4.1
Share repurchases, shares			0.1
Share repurchases	(1.8)		$ (1.8)
Other comprehensive income	3.1						2.9	0.2
Dividends and other changes in noncontrolling interest	(0.7)							(0.7)
Ending balance at Sep. 30, 2016	(118.4)	$ 0.7	$ (1.8)	0	3.6	0	(124.8)	3.9
Ending balance, shares at Sep. 30, 2016		71	0.1
Beginning balance at Dec. 31, 2016	(139)	$ 0.7	$ (2.1)	11	(4.7)		(147.6)	3.7
Beginning balance, shares at Dec. 31, 2016		71.2	0.1
Increase (Decrease) in Stockholders' Equity
Net income	637.8				637.6			0.2
Issuance of common stock in connection with stock plans, shares		0.1
Issuance of common stock in connection with stock plans	0	$ 0
Share-based compensation	7.5			7.5
Exercise of stock options, shares		0.4
Exercise of stock options	6.6			6.6
Share repurchases	(1)		$ (1)
Other comprehensive income	62.6						62.6
Dividends and other changes in noncontrolling interest	(2.3)							(2.3)
Ending balance at Sep. 30, 2017	$ 572.2	$ 0.7	$ (3.1)	$ 25.1	$ 632.9	$ 0	$ (85)	$ 1.6
Ending balance, shares at Sep. 30, 2017		71.7	0.1

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
OPERATING ACTIVITIES
Net income	$ 637.8	$ 70.3
Less: Income from discontinued operations	679.4	36.2
Income (loss) from continuing operations	(41.6)	34.1
Reconciliation to net cash (used in) provided by operating activities:
Depreciation and amortization	26.9	22.2
Amortization of debt discount and financing costs	2.2	2
Stock-based compensation expense	7.1	4.9
Gain on termination and curtailment of pension and other postretirement plans	(5.8)	(2.6)
Currency and other losses in Venezuela	40.1	2.9
Deferred income taxes	(5.6)	(10.5)
(Gain) loss on disposal of property and equipment	(0.6)	0.5
Loss on sale of product line	2.1	0
Changes in assets and liabilities, excluding effect of currency translation:
Trade accounts receivable	(40)	(28.6)
Inventories	(13.3)	(7.5)
Accounts payable	18.8	6.9
Pension assets and liabilities, net	7.2	3.4
Other assets and liabilities, net	(9.2)	(1.4)
Net cash (used in) provided by operating activities from continuing operations	(11.7)	26.3
Net cash (used in) provided by operating activities from discontinued operations	(15.3)	46.7
Net cash (used in) provided by operating activities	(27)	73
INVESTING ACTIVITIES
Capital expenditures	(32.4)	(30.5)
Businesses acquired, net of cash acquired	(87.7)	0
Proceeds from sale of product line	2.9	0
Other investing activities	2.4	0.5
Net cash used in investing activities from continuing operations	(114.8)	(30)
Net cash provided by (used in) investing activities from discontinued operations	1,038.3	(2.8)
Net cash provided by (used in) investing activities	923.5	(32.8)
FINANCING ACTIVITIES
Borrowings under credit arrangements	120	294.3
Repayments under credit arrangements	(416.6)	(30.7)
Proceeds from issuance of notes	0	525
Cash paid for debt financing costs	0	(18.2)
Share repurchases	(1)	(1.8)
Proceeds from exercise of stock options	6.1	3.7
Noncontrolling interest dividend	(2)	(0.7)
Transfers to parent, net	0	(758.7)
Net cash (used in) provided by financing activities from continuing operations	(293.5)	12.9
Net cash provided by (used in) financing activities from discontinued operations	1.1	(5.8)
Net cash (used in) provided by financing activities	(292.4)	7.1
Effect of currency exchange rate changes on cash and cash equivalents	4	2.6
Increase in cash and cash equivalents	608.1	49.9
Cash and cash equivalents, beginning of period	163.3	98.6
Cash and cash equivalents, end of period	771.4	148.5
Less: Cash and cash equivalents of discontinued operations	0	23.7
Cash and cash equivalents of continuing operations, end of period	$ 771.4	$ 124.8

Basis of Presentation and Summa

Basis of Presentation and Summary of Significant Accounting and Financial Reporting Policies	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Summary of Significant Accounting and Financial Reporting Policies	Basis of Presentation and Summary of Significant Accounting and Financial Reporting Policies On January 27, 2016, GCP entered into a separation and distribution agreement pursuant to which W.R. Grace & Co. ("Grace") agreed to transfer its Grace Construction Products operating segment and the packaging technologies business, operated under the “Darex” name, of its Grace Materials Technologies operating segment to GCP (the "Separation"). The Separation occurred on February 3, 2016, by means of a pro rata distribution to Grace stockholders of all of the then-outstanding shares of Company common stock, at which time GCP became an independent public company and its common stock listed and began trading under the symbol "GCP" on the New York Stock Exchange. On July 3, 2017, GCP completed the sale of its Darex Packaging Technologies ("Darex") business to Henkel AG & Co. KgaA (“Henkel”) for $1.06 billion in cash, subject to customary closing adjustments. As discussed further below under "Discontinued Operations," the results of operations for Darex have been excluded from continuing operations and segment results for all periods presented. GCP is engaged in the production and sale of specialty construction chemicals and specialty building materials through two operating segments. Specialty Construction Chemicals ("SCC") manufactures and markets concrete admixtures and cement additives. Specialty Building Materials ("SBM") manufactures and markets sheet and liquid membrane systems that protect structures from water, air and vapor penetration, fireproofing and other products designed to protect the building envelope. Basis of Presentation The accompanying Consolidated Financial Statements are presented on a consolidated basis and include all of the accounts and operations of GCP and its majority-owned subsidiaries, except as noted below with respect to the Company's Venezuela subsidiary. The financial statements reflect the financial position, results of operations and cash flows of GCP in accordance with generally accepted accounting principles in the United States of America ("GAAP") and with the instructions to Form 10-Q and Article 10 of SEC Regulation S-X for interim financial information. The interim 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 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 nine-month period ended September 30, 2017 are not necessarily indicative of the results of operations for the year ending December 31, 2017 . Discontinued Operations As noted above, on July 3, 2017, the Company completed the sale of Darex to Henkel. In conjunction with this transaction and applicable GAAP, the assets and liabilities related to Darex have been reclassified and reflected as "held for sale" on the Consolidated Balance Sheet as of December 31, 2016. As discussed further in Note 14, the assets and liabilities of the Darex business in certain delayed close countries are categorized as “Assets held for sale” or “Liabilities held for sale” in the accompanying Consolidated Balance Sheet as of September 30, 2017. Additionally, Darex has been reclassified and reflected as "discontinued operations" on the Consolidated Statements of Operations and Consolidated Statements of Cash Flows for all periods presented. GCP recognized a pre-tax gain on the sale of Darex of approximately $883.7 million during the third quarter of 2017. The calculation of the pre-tax gain excludes deferral of $68.7 million of consideration related to the delayed closings, which was received on the closing date. Deferred consideration is recorded in “Other current liabilities” and “Other liabilities” on the Consolidated Balance Sheet as of September 30, 2017. Unless otherwise noted, the information throughout the Notes to the Consolidated Financial Statements pertains only to the continuing operations of GCP. Refer to Note 14 for further discussion of the sale of Darex. Deconsolidation of Venezuelan Operations Prior to July 3, 2017, the Company included the results of its Venezuelan operations (“GCP Venezuela”) in the Consolidated Financial Statements using the consolidation method of accounting. Venezuelan exchange control regulations have resulted in an other-than-temporary lack of exchangeability between the Venezuelan bolivar and U.S. dollar, and have restricted GCP Venezuela’s ability to pay dividends and meet obligations denominated in U.S. dollars. These exchange regulations, combined with other recently adopted regulations, have constrained availability of raw materials and have significantly limited GCP Venezuela’s ability to maintain normal production. As a result of these conditions, combined with the loss of scale in Venezuela resulting from the sale of the Company’s Darex-related operations and assets in Venezuela, GCP has deconsolidated its Venezuelan operations as of July 3, 2017 in accordance with Financial Accounting Standards Board ("FASB") Accounting Standards Codification ("ASC") 810, Consolidation . Subsequent to this date, the Company began accounting for GCP Venezuela using the cost method of accounting. This change resulted in a third quarter 2017 pre-tax charge of $36.7 million ( $23.8 million net of tax), which is reflected in “Loss in Venezuela” in the accompanying Statement of Operations, primarily related to the recognition of $33.4 million of unfavorable cumulative translation adjustments associated with the Venezuelan business. In the third quarter of 2017, GCP recorded an out-period-adjustment to correct the misclassification of a $3.4 million foreign exchange remeasurement loss that was incorrectly included within discontinued operations in the second quarter of 2017. The impact of this correction, of which $2.9 million is reflected in "Loss on Venezuela" and $0.5 million is reflected in "Other income, net" on the Consolidated Statement of Operations, resulted in an increase in "Loss from continuing operations." There was no tax impact associated with this adjustment. There is no impact to the Consolidated Statement of Operations for the nine-month period ended September 30, 2017. GCP has assessed the impact of this error and concluded that the amount was not material to any prior-period financial statements and the impact of correcting this error in the current period is not material. In periods subsequent to July 3, 2017, the Company’s financial results will not include the operating results of GCP Venezuela. The Company will record cash and recognize income from its Venezuelan operations in the consolidated financial statements to the extent GCP is paid for inventory sold to or dividends received from GCP Venezuela. The remaining investment on the Company's Consolidated Balance Sheet as of September 30, 2017 is immaterial. Use of Estimates The preparation of financial statements in conformity with 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. GCP's accounting measurements that are most affected by management's estimates of future events are disclosed in its 2016 Annual Report on Form 10-K; there have been no significant changes to management's assumptions and estimates underlying those measurements as reported in these interim financial statements. Reclassifications Certain amounts in prior period financial statements have been reclassified to conform to the current period presentation. Such reclassifications have not materially affected previously reported amounts. Income Tax As a global enterprise, GCP is subject to a complex array of tax regulations and must make assessments of applicable tax law and judgments in estimating its ultimate income tax liability. Refer to Note 4 for details regarding estimates used in accounting for income tax matters including unrecognized tax benefits. Stock-Based Compensation Expense Prior to the Separation, GCP was allocated stock-based compensation expense from Grace related to GCP employees receiving awards denominated in Grace equity instruments. In accordance with an employee matters agreement entered into between Grace and GCP on January 27, 2016 in connection with the Separation (the "Employee Matters Agreement"), previously outstanding stock-based compensation awards granted under Grace's equity compensation programs prior to the Separation and held by certain executives and employees of GCP and Grace were adjusted to reflect the impact of the Separation on these awards. To preserve the aggregate intrinsic value of these stock-based compensation awards, as measured immediately before and immediately after the Separation, each holder of Grace stock-based compensation awards generally received an adjusted award consisting of either (i) both a stock-based compensation award denominated in Grace equity as it existed subsequent to the Separation and a stock-based compensation award denominated in GCP equity or (ii) solely a stock-based compensation award denominated in the equity of the company at which the person was employed following the Separation. In the Separation, the determination as to which type of adjustment applied to a holder’s previously outstanding Grace award was based upon the type of stock-based compensation award that was to be adjusted and the date on which the award was originally granted under the Grace equity compensation programs prior to the Separation. Under the Employee Matters Agreement, GCP retains certain obligations related to all stock- and cash-settled stock-based compensation awards denominated in GCP equity, regardless of whether the holder is a GCP or Grace employee. Following the Separation, the Company records stock-based compensation expense for equity awards in accordance with authoritative accounting guidance. Currency Translation Assets and liabilities of foreign subsidiaries (other than those located in countries with highly inflationary economies) are translated into U.S. dollars at current exchange rates, while revenues, costs and expenses are translated at average exchange rates during each reporting period. The resulting currency translation adjustments are included in accumulated other comprehensive income or loss in the Consolidated Balance Sheets. The financial statements of subsidiaries located in countries with highly inflationary economies are remeasured as if the functional currency were the U.S. dollar; the remeasurement creates translation adjustments that are reflected in net income in the Consolidated Statements of Operations. Recently Issued Accounting Standards Derivatives and Hedging In August 2017, the FASB issued Accounting Standards Update ("ASU") 2017-12, Derivatives and Hedging (Topic 815). The amendments in this update improve the financial reporting of hedging relationships to better portray the economic results of an entity's risk management activities in its financial statements by expanding and refining hedge accounting for both nonfinancial and financial risk components and aligning the recognition and presentation of the effects of the hedging instrument and the hedged item in the financial statements. The standard is effective for the Company as of January 1, 2019, and early adoption is permitted. GCP is currently evaluating the potential impact on its Consolidated Financial Statements and related disclosures, but does not expect the adoption of this standard will have a material effect on its Consolidated Financial Statements. Stock Compensation In May 2017, the FASB issued ASU 2017-09, Compensation—Stock Compensation (Topic 718), which provides guidance about which changes to the terms or conditions of a share-based payment award require an entity to apply modification accounting in Topic 718. The standard is effective for the Company on January 1, 2018, with early adoption permitted, including adoption in any interim period, for public business entities for reporting periods for which financial statements have not yet been issued. The amendments in this update should be applied prospectively to an award modified on or after the adoption date, and, therefore, GCP will consider the provisions of this update in conjunction with awards issued on or after January 1, 2018, as applicable. Goodwill In January 2017, the FASB issued ASU 2017-04, Intangibles—Goodwill and Other (Topic 350) . This ASU 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, which eliminates Step 2 from the goodwill impairment test. The standard is effective for the Company for annual or any interim goodwill impairment tests beginning on or after January 1, 2020. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. Revenue from Contracts with Customers In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606) . 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 revised 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. GCP will adopt the standard beginning January 1, 2018. GCP has preliminarily determined that it will adopt Topic 606 through a cumulative adjustment to retained earnings, as opposed to retrospectively adjusting prior periods, and continues to progress in its evaluation of the potential impact of the standard on its Consolidated Financial Statements and related disclosures. To date, a multi-disciplinary project team has analyzed certain of the Company's sales contracts and practices as compared to the new guidance and has begun to develop implementation steps to address the initial impact of adoption, including ongoing policy and process changes. In addition to the expanded disclosures regarding revenue, the guidance may affect the timing of revenue recognition for certain of the Company’s arrangements that involve multiple performance obligations, as well as arrangements containing variable consideration. Leases In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which 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. GCP is currently evaluating the potential impact on its Consolidated Financial Statements and related disclosures. Other new pronouncements issued but not effective until after September 30, 2017 are not expected to have a material impact on the Company's financial position, results of operations or liquidity. Recently Adopted Accounting Standards Business Combinations In January 2017, the FASB issued ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business , which clarifies the definition of a business when evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The update provides that when substantially all the fair value of the assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets, the transaction does not involve a business. The standard is effective for the Company on January 1, 2018, with early application permitted for certain transactions. GCP elected to early adopt the provisions of this update in the second quarter of 2017 in conjunction with its acquisition of Stirling Lloyd Plc (refer to Note 15). Pension and Other Postretirement Benefit Costs In March 2017, the FASB issued ASU 2017-07, Compensation—Retirement Benefits (Topic 715) : Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost, which changes certain presentation and disclosure requirements for employers that sponsor defined benefit pension and other postretirement benefit plans. The amendments in this ASU require entities to (1) report the service cost component of net periodic pension/postretirement benefit cost in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period; (2) capitalize only the service cost component of net periodic pension/postretirement benefit cost (when applicable); and (3) present other components of net periodic pension/postretirement benefit cost separately from the service cost component and outside a subtotal of income from operations (if applicable). The standard is effective for the Company on January 1, 2018, with early adoption permitted as of January 1, 2017. GCP elected to early adopt this standard in the first quarter of 2017 and has reflected only the service cost component of net periodic pension/postretirement benefit cost in "Cost of goods sold" and presented the other components of net periodic pension/postretirement benefit cost in "Other income, net," within the Consolidated Statements of Operations. In accordance with the standard, GCP utilized prior period footnote disclosures as a practical expedient to apply these retrospective presentation requirements and will prospectively apply the capitalization requirements. GCP's adoption of this standard did not have a material effect on the accompanying Consolidated Financial Statements. Inventory In July 2015, the FASB issued ASU 2015-11, Simplifying the Measurement of Inventory . The update requires that inventory be measured at the lower of cost or net realizable value for entities using first-in, first-out ("FIFO") 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. GCP adopted this standard for the 2017 first quarter and there were no material effects on the accompanying Consolidated Financial Statements.

Inventories

Inventories	9 Months Ended
	Sep. 30, 2017
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories are stated at the lower of cost or net realizable value. GCP determines cost using the FIFO methodology. Inventories presented on GCP's Consolidated Balance Sheets consisted of the following: (In millions) September 30, December 31, Raw materials $ 40.2 $ 35.7 In process 4.0 3.6 Finished products and other 64.2 50.0 Total inventories $ 108.4 $ 89.3 Included above as "other" within "Finished products and other" are finished products purchased rather than produced by GCP of $12.2 million and $10.9 million as of September 30, 2017 and December 31, 2016 , respectively.

Debt and Other Financial Instru

Debt and Other Financial Instruments	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
Debt and Other Financial Instruments	Debt and Other Financial Instruments Components of Debt (In millions) September 30, December 31, 9.5% Senior Notes due 2023, net of unamortized debt issuance costs of $6.6 at September 30, 2017 (2016 — $7.3) $ 518.4 $ 517.7 Term Loan due 2022, net of unamortized discount of $2.4M and unamortized debt issuance costs of $4.3M at December 31, 2016 (1) — 266.2 Revolving credit facility due 2021 (2) — 25.0 Other borrowings (3) 25.7 22.0 Total debt 544.1 830.9 Less debt payable within one year 23.8 47.9 Debt payable after one year $ 520.3 $ 783.0 Weighted average interest rates on total debt 9.4 % 7.5 % __________________________ (1) GCP repaid the outstanding principal balance and accrued interest on the Term Loan in July 2017. Refer below to "Credit Agreement" disclosure. (2) Interest at LIBOR + 200 bps at September 30, 2017 . (3) Represents borrowings under various lines of credit and other borrowings, primarily by non-U.S. subsidiaries. The principal maturities of debt outstanding (net of unamortized discounts and debt issuance costs) at September 30, 2017 , were as follows: (In millions) 2017 $ 23.4 2018 0.9 2019 0.9 2020 0.5 2021 — Thereafter 518.4 Total debt $ 544.1 Credit Agreement On February 3, 2016, GCP entered into a credit agreement (the “Credit Agreement”) that provides for senior secured credit facilities (the “Credit Facilities”) in an aggregate principal amount of $525.0 million , consisting of: (a) term loan (the “Term Loan”) in an aggregate principal amount of $275.0 million maturing in 2022; and (b) $250.0 million revolving credit facility (the "Revolving Loan") due in 2021. The Credit Agreement contains customary affirmative covenants, including, but not limited to (i) maintenance of legal existence and compliance with laws and regulations; (ii) delivery of consolidated financial statements and other information; (iii) payment of taxes; (iv) delivery of notices of defaults and certain other material events; and (v) maintenance of adequate insurance. The Credit Agreement also contains customary negative covenants, including but not limited to restrictions on (i) dividends on, and redemptions of, equity interests and other restricted payments; (ii) liens; (iii) loans and investments; (iv) the sale, transfer or disposition of assets and businesses; (v) transactions with affiliates; and (vi) a maximum total leverage ratio. Certain debt covenants may restrict the entity's ability as it relates to dividends, acquisitions and other borrowings. The Credit Agreement contains conditions that would require mandatory principal payments in advance of the maturity date of the Term Loan and Revolving Loan; the Company was in compliance with all terms as of September 30, 2017 . Events of default under the Credit Agreement include, but are not limited to: (i) failure to pay principal, interest, fees or other amounts under the Credit Agreement when due, taking into account any applicable grace period; (ii) any representation or warranty proving to have been incorrect in any material respect when made; (iii) failure to perform or observe covenants or other terms of the Credit Agreement subject to certain grace periods; (iv) a cross-default and cross-acceleration with certain other material debt; (v) bankruptcy events; (vi) certain defaults under ERISA; and (vii) the invalidity or impairment of security interests. There are no events of default as of September 30, 2017 . The Credit Facilities are secured on a first priority basis by a perfected security interest in, and mortgages on, substantially all tangible and intangible personal property and material fee-owned real property (specifically properties in Chicago, Illinois and Mount Pleasant, Tennessee) of the Company, a pledge of 100% of the equity of each material U.S. subsidiary of the Company and 65% of the equity of the United Kingdom holding company. During 2016, GCP refinanced the existing Credit Agreement with a syndicate of banks (the “First Amendment to Credit Agreement”). The First Amendment to Credit Agreement reduced the interest rate margins applicable to the Term Loan from base rate plus a margin of 3.5% or LIBOR plus a margin of 4.5% to a base rate plus a margin of 2.25% or LIBOR plus a margin of 3.25% at GCP’s option. The outstanding principal balance was replaced by a like aggregate principal balance with substantially similar terms to the Credit Agreement. On July 31, 2017, the Company repaid the outstanding principal balance and extinguished the Term Loan under the Credit Agreement, which, together with accrued and unpaid interest, was $272.6 million . In conjunction with the debt repayment, GCP wrote-off the net unamortized discount of $2.1 million and the net unamortized debt issuance costs of $3.9 million related to the Term Loan, which are reflected in "Interest expense and related financing costs" in the Consolidated Statement of Operations for the three and nine months ended September 30, 2017. The interest rate per annum applicable to the Revolving Loan is equal to, at GCP’s option, either a base rate plus a margin ranging from 0.5% to 1.0% or LIBOR plus a margin ranging from 1.5% to 2.0% , in either case based upon the total leverage ratio of GCP and its restricted subsidiaries. As of September 30, 2017 , there were no outstanding draws and approximately $10 million in outstanding letters of credit, which resulted in available credit under the Revolving Loan of $240.0 million . The summary above of the Credit Agreement and First Amendment to Credit Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of such agreements, copies of which have been filed with the SEC. Senior Notes On January 27, 2016, GCP issued $525.0 million aggregate principal amount of 9.5% Senior Notes due 2023 (the “Notes”). Interest is payable semi-annually in arrears on February 1 and August 1 of each year. The Notes were issued subject to covenants that limit the Company's and certain of its subsidiaries’ ability, subject to certain exceptions and qualifications, to (i) create or incur liens on assets; (ii) incur additional debt; (iii) sell certain assets; and/or (iv) make certain investments and acquisitions, merge or sell or otherwise dispose of all or substantially all assets. Other Items As discussed in Note 1, on July 3, 2017, the Company completed the sale of Darex to Henkel for $1.06 billion , subject to working capital and certain other adjustments. The sale of Darex is a permitted transaction under the Company's Credit Agreement and the Indenture governing the Notes. Under the Credit Agreement and Indenture, the Company is required to use any net cash proceeds from the sale of Darex to prepay debt or make investments in its business over a period of approximately 18 months . Refer to Note 14 for further discussion of the sale of Darex. During 2016, GCP incurred debt issuance costs relating to issuance of the Notes, Term Loan and Revolving Loan of $8.0 million , $5.0 million and $5.2 million , respectively. GCP deducted the debt issuance costs relating to the Notes and the Term Loan from the carrying amounts presented on its Consolidated Balance Sheets and continues to amortize the costs related to the Notes over the term of the underlying obligation. GCP classified the debt issuance costs relating to the Revolving Loan in "Other assets" on its Consolidated Balance Sheets and is amortizing those costs over the term of the Revolving Loan. The unamortized portion of these costs reflected in "Other assets" was $3.5 million as of September 30, 2017 and $4.2 million as of December 31, 2016 . During the first quarter of 2016, GCP used certain proceeds from the Notes and Credit Facilities to fund a distribution to Grace in an amount of $750.0 million related to the Separation. Approximately $50 million was retained to meet operating requirements and to pay fees associated with the debt financing and other costs of the Separation. Related party debt of approximately $42 million and related interest was transferred from Grace to GCP in connection with the Separation. Debt Fair Value At September 30, 2017 , the carrying amounts and fair values of GCP's debt were as follows: September 30, 2017 December 31, 2016 (In millions) Carrying Amount Fair Value Carrying Amount Fair Value 9.5% Senior Notes due 2023 $ 518.4 $ 592.6 $ 517.7 $ 603.1 Term Loan due 2022 — — 266.2 274.6 Revolving credit facility due 2021 — — 25.0 25.0 Other borrowings 25.7 25.7 22.0 22.0 Total debt $ 544.1 $ 618.3 $ 830.9 $ 924.7 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. The decrease in fair value on the Senior Notes as of September 30, 2017 was due primarily to the Federal Reserve raising the federal funds target rate during 2017 .

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The income tax benefit attributable to continuing operations for the three months ended September 30, 2017 was $14.5 million , compared with income tax expense attributable to continuing operations of $2.5 million for the three months ended September 30, 2016, representing effective tax rates of 44.6% and 18.4% , respectively. The income tax expense attributable to continuing operations for the nine months ended September 30, 2017 and 2016 was $3.7 million and $9.8 million , respectively, representing effective tax rates of 9.8% and 22.3% , respectively. The difference between the provision for income taxes at the U.S. federal income tax rate of 35% and GCP’s overall income tax rate is summarized below. Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Income tax (benefit) expense at U.S. federal income tax rate $ (11.4 ) $ 4.8 $ (13.3 ) $ 15.4 Change in income tax (benefit) expense resulting from: Valuation allowance — — 13.9 — Tax on undistributed foreign earnings (2.9 ) — 3.6 — Effect of tax rates in foreign jurisdictions (0.1 ) (0.5 ) 0.1 (3.9 ) Permanent items and other (0.1 ) (1.8 ) (0.6 ) (1.7 ) Income tax (benefit) expense $ (14.5 ) $ 2.5 $ 3.7 $ 9.8 For the three months ended September 30, 2017 and 2016, GCP recorded income tax expense attributable to discontinued operations of $ 200 million and $7.1 million , respectively. For the nine months ended September 30, 2017 and 2016, GCP recorded income tax expense attributable to discontinued operations of $ 199.7 million and $ 20.0 million , respectively. Refer to Note 14 for further details regarding the Darex transaction. As of December 31, 2016, GCP had the intent and ability to indefinitely reinvest undistributed earnings of its foreign subsidiaries outside the United States. During the first and second quarters of 2017, GCP determined it could no longer assert it is indefinitely reinvested in Mexico and Venezuela because these entities were included in the Darex transaction, resulting in a tax expense of $6.5 million . In the third quarter of 2017, GCP recorded $7.5 million of tax benefit related to an adjustment to the Mexico outside book and tax basis difference. Additionally, in the third quarter of 2017, pursuant to tax planning with the respect to the Company’s subsidiary, GCP UK Holdings Limited, GCP determined it could no longer assert it is indefinitely reinvested in this subsidiary, resulting in $4.6 million of tax expense. These changes in assertions resulted in a tax benefit of $2.9 million in the third quarter of 2017 and tax expense of $3.6 million for the nine months ended September 30, 2017. Management is in the process of completing further analysis related to the stock basis, earnings and profits, tax pools, and other related components associated with the Darex transaction. Based on the overall complexity of the calculation, management believes that there is a reasonable possibility that differences between these estimates and actual outcomes may result within the next 12 months, which could have a material impact on the Company’s consolidated financial position. GCP believes that the sale of Darex is a one-time, non-recurring event and that recognition of deferred taxes of undistributed earnings during 2017 would not have occurred if not for the sale. As of September 30, 2017 , GCP has the intent and ability to indefinitely reinvest undistributed earnings of all its other foreign subsidiaries outside the United States. GCP expects undistributed prior-year earnings of its foreign subsidiaries to remain indefinitely reinvested except in certain instances where repatriation of such earnings would result in minimal or no tax. GCP bases this assertion on: (1) the expectation that it will satisfy its U.S. cash obligations in the foreseeable future without requiring the repatriation of prior-year foreign earnings; (2) plans for significant and continued reinvestment of foreign earnings in organic and inorganic growth initiatives outside the U.S.; and (3) remittance restrictions imposed by local governments. GCP will continually analyze and evaluate its cash needs to determine the appropriateness of its indefinite reinvestment assertion. In evaluating GCP's ability to realize its deferred tax assets, GCP 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 GCP for tax reporting purposes in the related jurisdiction. In estimating future taxable income, GCP relies upon assumptions and estimates about future activities, including the amount of future federal, state and foreign pretax operating income that GCP will generate; the reversal of temporary differences; and the implementation of feasible and prudent tax planning strategies. GCP records a valuation allowance to reduce deferred tax assets to the amount that it believes is more likely than not to be realized. GCP determined it is more likely than not a portion of its deferred tax assets will not be realized. As a result, GCP recorded valuation allowances on those deferred tax assets as discrete items, as they are significant, unusual and infrequent in nature. The $13.9 million valuation allowance recorded for the nine months ended September 30, 2017 relates to U.S. foreign tax credit carryovers and Brazil and Turkey deferred tax assets relating primarily to net operating loss carryovers. The determination to record the valuation allowances was made predominantly due to the sale of Darex and its impact on future taxable income and the ability to utilize those tax assets. In connection with the Separation, GCP and Grace entered into various agreements that govern the relationship between the parties going forward, including a tax matters agreement (the "Tax Sharing Agreement"). Under the Tax Sharing Agreement, which was entered into on the distribution date, GCP and Grace will indemnify and hold each other harmless in accordance with the principles outlined therein.

Pension Plans and Other Postret

Pension Plans and Other Postretirement Benefit Plans	9 Months Ended
	Sep. 30, 2017
Pension and Other Postretirement Benefits Cost (Reversal of Cost) [Abstract]
Pension Plans and Other Postretirement Benefit Plans	Pension Plans and Other Postretirement Benefit Plans Postretirement Benefits Other Than Pensions Prior to the Separation, Grace provided postretirement life insurance benefits for retired employees of certain U.S. business units and certain divested business units. During the second quarter of 2016, GCP entered into an agreement to eliminate retiree life insurance benefits for one of its two remaining bargaining locations. This plan change was a negative plan amendment that resulted in a $1.0 million curtailment gain, which is presented in "Other income, net" in the Consolidated Statements of Operations for the nine months ended September 30, 2016 . Pension Plans GCP sponsors certain defined benefit pension plans, primarily in the U.S. and the U.K., in which GCP employees participate. GCP records an asset or liability to recognize the funded status of these pension plans in its Consolidated Balance Sheets. The following table presents the funded status of GCP's overfunded, underfunded and unfunded defined pension plans from continuing operations: (In millions) September 30, December 31, Overfunded defined benefit pension plans $ 22.1 $ 21.2 Underfunded defined benefit pension plans (57.9 ) (55.6 ) Unfunded defined benefit pension plans (27.7 ) (27.6 ) Total underfunded and unfunded defined benefit pension plans (85.6 ) (83.2 ) Pension liabilities included in other current liabilities (1.0 ) (0.4 ) Net funded status $ (64.5 ) $ (62.4 ) Overfunded plans include several advance-funded plans for which the fair value of the plan assets exceeds the projected benefit obligation ("PBO"). This group of plans was overfunded by $22.1 million as of September 30, 2017 , and the overfunded status is reflected as assets in "Overfunded defined benefit pension plans" in the Consolidated Balance Sheets. Underfunded plans include a group of advance-funded plans that are underfunded on a PBO basis. Unfunded plans include several plans that are funded on a pay-as-you-go basis, and therefore, the entire PBO is unfunded. As of September 30, 2017 , the combined balance of $86.6 million for the underfunded and unfunded plans included as liabilities in the Consolidated Balance Sheets is comprised of current and non-current components of $1.0 million in "Other current liabilities" and $85.6 million in "Underfunded and unfunded defined benefit pension plans," respectively. On May 3, 2017, the Board of Directors approved an amendment to the GCP Applied Technologies Inc. Retirement Plan for Salaried Employees that closes the plan to new hires effective January 1, 2018 and freezes the accrual of plan benefits for all plan participants as of December 31, 2022. In the second quarter of 2017, the Company recognized a curtailment gain of $5.1 million in continuing operations and $0.5 million in discontinued operations as a result of this plan amendment. In addition, GCP terminated and settled a pension plan at one non-U.S. location, resulting in a mark-to-market remeasurement gain of $0.1 million . With the exception of the $0.5 million recorded in discontinued operations, these amounts are presented in "Other income, net" in the Consolidated Statements of Operations for the nine months ended September 30, 2017 . In the third quarter of 2017 , the Company recognized a curtailment gain of $0.7 million as a result of restructuring activities in the U.S. presented in "Other income, net" in the Consolidated Statements of Operations for the three and nine months ended September 30, 2017 . In connection with the Company's divestiture of the Darex segment in the third quarter of 2017, the Company recognized curtailment and settlement gains totaling $2.1 million and $14.3 million relating to the defined benefit pension plans in the U.S. and outside of the U.S, respectively. These amounts are presented in "Income from discontinued operations, net of income taxes" in the Consolidated Statements of Operations for the three and nine months ended September 30, 2017 . The Company also incurred mark-to-market losses associated with the divestiture of Darex as a result of the remeasurement of plan assets and projected benefit obligations of $1.2 million and $1.8 million for the U.S. plans and non-U.S. plans, respectively, which are presented in "Other income, net" (as a component of continuing operations) in the Consolidated Statements of Operations for the three and nine months ended September 30, 2017 . In addition to the amounts disclosed above, the Company has included in "Income from discontinued operations, net of income taxes" a $0.1 million mark-to-market gain in the third quarter of 2017 and $0.5 million of non-U.S. plan service cost, interest cost, and expected return on plan assets for the nine months ended September 30, 2017 , as well as $0.3 million and $0.9 million of non-U.S. plan service cost, interest cost, and expected return on plan assets for the three and nine months ended September 30, 2016 , respectively. Components of Net Periodic Benefit Cost (Income) Three Months Ended September 30, 2017 2016 Pension Pension (In millions) U.S. Non-U.S. Other Post U.S. Non-U.S. Other Post Service cost $ 1.6 $ 0.8 $ — $ 1.6 $ 0.8 $ — Interest cost 1.3 1.4 — 1.1 1.9 — Expected return on plan assets (1.4 ) (1.6 ) — (1.2 ) (2.1 ) — Amortization of net deferred actuarial loss — — — — — 0.1 Mark-to-market adjustment 1.2 1.7 — — — — Gain on curtailments, settlements and terminations (2.8 ) (14.3 ) — — (0.2 ) — Net periodic benefit (income) cost $ (0.1 ) $ (12.0 ) $ — $ 1.5 $ 0.4 $ 0.1 Less: Discontinued operations (income) cost (2.1 ) (14.4 ) — — 0.3 — Net periodic benefit cost from continuing operations $ 2.0 $ 2.4 $ — $ 1.5 $ 0.1 $ 0.1 Nine Months Ended September 30, 2017 2016 Pension Pension (In millions) U.S. Non-U.S. Other Post U.S. Non-U.S. Other Post Service cost $ 5.3 $ 3.0 $ — $ 4.6 $ 2.5 $ — Interest cost 4.2 4.3 — 3.5 6.0 — Expected return on plan assets (4.2 ) (5.1 ) — (3.7 ) (6.6 ) — Amortization of prior service credit — — — — — (0.1 ) Amortization of net deferred actuarial loss — — — — — 0.1 Mark-to-market adjustment 1.2 1.6 — — — — Gain on termination and curtailment of pension and other postretirement plans (8.4 ) (14.3 ) — — (1.6 ) (1.0 ) Net periodic benefit (income) cost $ (1.9 ) $ (10.5 ) $ — $ 4.4 $ 0.3 $ (1.0 ) Less: Discontinued operations (income) cost (2.6 ) (13.9 ) — — 0.9 — Net periodic benefit cost (income) from continuing operations $ 0.7 $ 3.4 $ — $ 4.4 $ (0.6 ) $ (1.0 ) Plan Contributions and Funding GCP intends to satisfy its funding obligations to U.S. tax-qualified pension plans and to comply with all of the requirements of the Employee Retirement Income Security Act of 1974, as amended ("ERISA"). For ERISA purposes, funded status is calculated on a different basis than under GAAP. GCP intends to fund non-U.S. pension plans based on applicable legal requirements as well as actuarial and trustee recommendations. GCP contributed $1.9 million to these non-U.S. plans during the nine months ended September 30, 2017 compared with $1.7 million during the prior-year period . Defined Contribution Retirement Plan As part of the Separation, GCP established a defined contribution retirement plan for its employees in the U.S. This plan is intended to be tax-qualified under section 401(k) of the Internal Revenue Code of 1986, as amended. Currently, GCP contributes to the 401(k) plan an amount equal to 100% of an employee's contributions to the plan, up to 6% of such employee's eligible compensation. GCP's costs included in "Selling, general and administrative expenses" in the Consolidated Statements of Operations related to this plan for the three and nine months ended September 30, 2017 were $1.1 million and $3.6 million compared with $1.0 million and $3.0 million during the prior-year period s, respectively.

Other Balance Sheet Accounts

Other Balance Sheet Accounts	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Other Balance Sheet Accounts	Other Balance Sheet Accounts (In millions) September 30, December 31, Other Current Assets: Non-trade receivables $ 36.1 $ 19.9 Income tax receivable 7.4 10.6 Prepaid and other 15.7 12.4 Total other current assets $ 59.2 $ 42.9 (In millions) September 30, December 31, Other Current Liabilities Customer volume rebates $ 28.6 $ 30.5 Accrued compensation (1) 23.0 28.0 Income tax payable 118.2 6.7 Accrued interest 8.5 20.8 Restructuring liabilities 15.2 1.1 Pension liabilities 1.0 0.4 Other accrued liabilities (2) 115.8 32.0 Total other current liabilities $ 310.3 $ 119.5 ________________________________ (1) Accrued compensation in the table above includes salaries and wages, as well as estimated current amounts due under the annual and long-term incentive programs. (2) Other accrued liabilities in the table above as of September 30, 2017 includes $55.1 million of deferred consideration related to the delayed closings associated with our divestiture of Darex, as discussed in Note 14.

Commitments and Contingent Liab

Commitments and Contingent Liabilities	9 Months Ended
	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingent Liabilities	Commitments and Contingent Liabilities Purchase Commitments GCP uses purchase commitments to ensure supply and to minimize the volatility of certain key raw materials including lignins, polycarboxylates, amines and other materials. Such commitments are for quantities that GCP fully expects to use in its normal operations. Guarantees and Indemnification Obligations GCP 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. GCP accrues a general warranty liability at the time of sale based on historical experience and on a transaction-specific basis according to individual facts and circumstances. Both the liability and annual expense related to product warranties are immaterial to the Consolidated Financial Statements. • Performance guarantees offered to customers. GCP has not established a liability for these arrangements based on past performance. • Contracts providing for the sale of a business unit or product line in which GCP has agreed to indemnify the buyer against liabilities arising prior to the closing of the transaction, including environmental liabilities. • The Tax Sharing Agreement requires GCP, in certain circumstances, to indemnify Grace if the Separation, together with certain related transactions, does not qualify under Section 355 and certain other relevant provisions of the Internal Revenue Code (the "Code"). If GCP is required to indemnify Grace under the Tax Sharing Agreement, it could be subject to significant tax liabilities. Environmental Matters GCP is subject to loss contingencies resulting from extensive and evolving federal, state, local and foreign environmental laws and regulations relating to the generation, storage, handling, discharge, disposition and stewardship of hazardous wastes and other materials. GCP accrues for anticipated costs associated with response efforts where an assessment has indicated that a probable liability has been incurred and the cost can be reasonably estimated. As of September 30, 2017 , GCP did not have any material environmental liabilities. GCP's environmental liabilities are reassessed whenever circumstances become better defined or response efforts and their costs can be better estimated. These liabilities are evaluated based on currently available information, including the progress of remedial investigations at each site, the current status of discussions with regulatory authorities regarding the method and extent of remediation at each site, existing technology, prior experience in contaminated site remediation and the apportionment of costs among potentially responsible parties. Financial Assurances Financial assurances have been established for a variety of purposes, including insurance and environmental matters and other matters. At September 30, 2017 , GCP had gross financial assurances issued and outstanding of approximately $10 million , composed of standby letters of credit. Lawsuits and Investigations In Re: Library Gardens Balcony Litigation, Lead Case Beary v. Blackrock, Inc. Case No. RG15793054 was filed on November 12, 2015 in Alameda County Superior Court in California. It is the lead case in a consolidated lawsuit filed on behalf of six individuals who died and an additional seven individuals who were injured in a balcony collapse, which occurred on June 16, 2015 in Berkeley, California. The consolidated complaint names the Company as the sole party in the category of suppliers of materials and names twenty additional defendants in other categories, including categories for property owners, property managers, construction defendants and development and design defendants. The consolidated complaint alleges product liability against the Company concerning one of its products. The plaintiffs seek unspecified monetary damages against all defendants and punitive damages only against the building owners, building manager and two construction company defendants. During the third quarter of 2017, the Company reached an agreement with the plaintiffs to settle this matter for $4.0 million , which the Company has recorded and reflected in "Selling, general and administrative expenses" in the accompanying Consolidated Statements of Operations. The settlement documents have been distributed to the parties for signature. Once all signatures have been obtained, the settlement will be presented to the court for approval. In addition to the above, from time to time, GCP and its subsidiaries are parties to, or targets of, lawsuits, claims, investigations and proceedings which are managed and defended in the ordinary course of business. While GCP is unable to predict the outcome of these matters, it does not believe, based upon currently available facts, that the ultimate resolution of any of such pending matters will have a material adverse effect on its overall financial condition, results of operations or cash flows. Accounting for Contingencies Although the outcome of each of the matters discussed above cannot be predicted with certainty, GCP has assessed its risk and has made accounting estimates and disclosures as required under GAAP.

Restructuring and Repositioning

Restructuring and Repositioning Expenses	9 Months Ended
	Sep. 30, 2017
Restructuring and Related Activities [Abstract]
Restructuring and Repositioning Expenses	Restructuring and Repositioning Expenses GCP's Board of Directors approves all major restructuring programs that may involve the discontinuance of significant product lines or the shutdown of significant facilities. From time to time, GCP takes additional restructuring actions, including involuntary employee terminations that are not part of a major program. Restructuring programs generally include severance and other employee-related costs, contract or lease termination costs, asset impairments, facility exit costs and other costs. The Company may also undertake repositioning activities that generally represent major strategic or transformational actions to enhance the value and performance of the Company, improve business efficiency or optimize the Company’s footprint. Repositioning expenses generally include professional fees, such as recruitment, consulting and legal fees and other associated costs that are not classified as restructuring expenses. GCP accounts for these costs, which are reflected in "Restructuring expenses and asset impairments" and “Repositioning expenses,” respectively, in its Consolidated Statements of Operations, or in those captions within discontinued operations, in the period that the related liabilities are incurred. Restructuring expenses, including asset impairments, and repositioning expenses are excluded from segment operating income. 2017 Restructuring and Repositioning Plan (the “2017 Plan”) On June 28, 2017, the Board of Directors approved a restructuring and repositioning plan that includes actions to streamline its operations, reduce its global cost structure and reposition itself as a construction products technologies company. The Company expects to incur total costs under the 2017 Plan of approximately $28 million to $32 million , an increase from the $22 million to $26 million estimated range in the second quarter of 2017. The 2017 Plan includes approximately $25 million related to restructuring activities and approximately $6 million related to repositioning activities. The restructuring activities, which are expected to be completed by December 31, 2018, primarily relate to severance and other employee-related costs, asset impairments and facility exit costs, of which the Company expects to classify approximately $9 million within discontinued operations. The repositioning activities primarily include consulting, other professional services and recruitment costs associated with the Company’s organizational realignment. In addition, the Company expects to incur approximately $9 million in capital expenditures related to repositioning activities, an increase of $3 million from the estimate in the second quarter of 2017. All of the Company’s repositioning activities are expected to relate to continuing operations and should be substantially completed by December 31, 2019. The Company expects to settle substantially all of the costs related to the 2017 Plan in cash. Restructuring Expenses The following table summarizes restructuring expenses incurred related to the 2017 Plan and prior-period plans: Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Severance and other employee costs $ 2.1 $ 0.4 $ 19.0 $ 1.4 Facility exit costs and asset impairments 0.4 — 0.9 — Total restructuring expenses $ 2.5 $ 0.4 $ 19.9 $ 1.4 Less: restructuring expenses reflected in discontinued operations 0.4 — 6.9 — Total restructuring expenses from continuing operations $ 2.1 $ 0.4 $ 13.0 $ 1.4 GCP incurred restructuring costs related to its segments as follows: Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 SCC $ 0.7 $ 0.3 $ 6.2 $ 0.8 SBM (0.3 ) 0.1 4.1 0.6 Corporate 1.7 — 2.7 — Total restructuring expenses from continuing operations $ 2.1 $ 0.4 $ 13.0 $ 1.4 Restructuring expenses reflected in discontinued operations 0.4 — 6.9 — Total restructuring expenses $ 2.5 $ 0.4 $ 19.9 $ 1.4 GCP had restructuring liabilities of $15.2 million and $1.1 million as of September 30, 2017 and December 31, 2016, respectively. These liabilities are included within “Other current liabilities” and “Other liabilities” in the Consolidated Balance Sheets. GCP expects to pay substantially all costs related to prior-year plans by December 31, 2017 and the 2017 Plan by December 31, 2018. The following table summarizes details of the Company’s restructuring liability activity: 2017 Plan (In millions) Severance and other employee costs Facility exit costs Other plans Total Balance, December 31, 2016 $ — $ — $ 1.1 $ 1.1 Expense 18.5 0.1 0.5 19.1 Payments (4.7 ) — (0.5 ) (5.2 ) Impact of foreign currency and other 0.2 — — 0.2 Balance, September 30, 2017 $ 14.0 $ 0.1 $ 1.1 $ 15.2 Repositioning Expenses Repositioning Expenses - 2017 Plan Repositioning expenses associated with the 2017 Plan primarily relate to consulting, other professional services and recruitment costs associated with the Company’s organizational realignment. Due to the scope and complexity of the Company’s repositioning activities, the range of estimated repositioning expense could increase or decrease and the timing of incurrence could change. For the three months ended September 30, 2017 , GCP incurred repositioning expenses related to the 2017 Plan of $1.1 million , substantially all of which represent professional fees and employee-related costs. Total expenses for the nine months ended September 30, 2017 were $1.5 million . Total cash payments for the nine months ended September 30, 2017 were $1.2 million . Separation-Related Repositioning Expenses Post-Separation from Grace, GCP incurred expenses related to its transition to a stand-alone public company. As of June 30, 2017, the Company has substantially completed these activities and incurred total costs of $20.5 million . Separation-related repositioning expenses primarily relate to the following: • accounting, tax, legal and other professional costs pertaining to the Separation and establishment as a stand-alone public company; • costs relating to information technology systems and marketing expense for repackaging and re-branding; • employee-related costs that would not be incurred absent the Separation primarily relating to compensation, benefits, retention bonuses related to new or transitioning employees; and • recruitment and relocation costs associated with hiring and relocating employees. Separation-related repositioning expenses incurred for the periods presented were as follows: Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Professional fees $ — $ 3.1 $ 3.4 $ 7.3 Software and IT implementation fees — 0.8 0.9 2.5 Employee-related costs — 1.4 1.0 4.5 Total $ — $ 5.3 $ 5.3 $ 14.3 Total cash payments for the nine months ended September 30, 2017 were $4.2 million for professional fees and employee-related costs and $1.9 million for related capital expenditures. Total cash payments for the nine months ended September 30, 2016 were $14.7 million for professional fees and employee-related costs, $5.7 million for related capital expenditures and $6.9 million for taxes.

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Other Comprehensive Income (Loss)	Other Comprehensive Income (Loss) The following tables present the pre-tax, tax and after-tax components of GCP's other comprehensive income for the three and nine months ended September 30, 2017 and 2016 : Three Months Ended September 30, 2017 (In millions) Pre-Tax Amount Tax (Expense)/ Benefit After-Tax Amount Defined benefit pension and other postretirement plans: Other changes $ (0.3 ) $ — $ (0.3 ) Benefit plans, net (0.3 ) — (0.3 ) Currency translation adjustments 46.2 — 46.2 Gain from hedging activities 0.8 (0.3 ) 0.5 Other comprehensive income attributable to GCP shareholders $ 46.7 $ (0.3 ) $ 46.4 Nine Months Ended September 30, 2017 (In millions) Pre-Tax Amount Tax (Expense)/ Benefit After-Tax Amount Defined benefit pension and other postretirement plans: Other changes $ (0.3 ) $ — $ (0.3 ) Benefit plans, net (0.3 ) — (0.3 ) Currency translation adjustments 63.0 — 63.0 Loss from hedging activities (0.1 ) — (0.1 ) Other comprehensive income attributable to GCP shareholders $ 62.6 $ — $ 62.6 Three Months Ended September 30, 2016 (In millions) Pre-Tax Amount Tax (Expense)/ Benefit After-Tax Amount Defined benefit pension and other postretirement plans: Amortization of net actuarial gain $ 0.1 $ — $ 0.1 Other changes in funded status (0.1 ) — (0.1 ) Benefit plans, net — — — Currency translation adjustments 3.0 — 3.0 Loss from hedging activities (0.1 ) — (0.1 ) Other comprehensive income attributable to GCP shareholders $ 2.9 $ — $ 2.9 Nine Months Ended September 30, 2016 (In millions) Pre-Tax Amount Tax (Expense)/ Benefit After-Tax Amount Defined benefit pension and other postretirement plans: Amortization of net prior service credit $ (0.1 ) $ — $ (0.1 ) Amortization of net actuarial gain 0.1 — 0.1 Assumption of net prior service credit 1.2 (0.4 ) 0.8 Assumption of net actuarial loss (1.1 ) 0.4 (0.7 ) Other changes in funded status (0.9 ) 0.3 (0.6 ) Benefit plans, net (0.8 ) 0.3 (0.5 ) Currency translation adjustments 3.5 — 3.5 Loss from hedging activities (0.1 ) — (0.1 ) Other comprehensive income attributable to GCP shareholders $ 2.6 $ 0.3 $ 2.9 The following tables present the changes in accumulated other comprehensive income (loss), net of tax, for the nine months ended September 30, 2017 and 2016 : Nine Months Ended September 30, 2017 (In millions) Defined Benefit Pension and Other Postretirement Plans Currency Translation Adjustments (Losses) Gains from Hedging Activities Total Beginning balance $ 0.1 $ (147.7 ) $ — $ (147.6 ) Other comprehensive (loss) income before reclassifications (0.3 ) 63.0 (0.7 ) 62.0 Amounts reclassified from accumulated other comprehensive (loss) income — — 0.6 0.6 Net current-period other comprehensive (loss) income (0.3 ) 63.0 (0.1 ) 62.6 Ending balance $ (0.2 ) $ (84.7 ) $ (0.1 ) $ (85.0 ) Nine Months Ended September 30, 2016 (In millions) Defined Benefit Pension and Other Postretirement Plans Currency Translation Adjustments (Losses) Gains from Hedging Activities Total Beginning balance $ 0.1 $ (127.8 ) $ — $ (127.7 ) Other comprehensive income (loss) before reclassifications — 3.5 (1.2 ) 2.3 Amounts reclassified from accumulated other comprehensive income (loss) (0.5 ) — 1.1 0.6 Net current-period other comprehensive (loss) income (0.5 ) 3.5 (0.1 ) 2.9 Ending balance $ (0.4 ) $ (124.3 ) $ (0.1 ) $ (124.8 ) GCP is a global enterprise operating in over 35 countries with local currency generally deemed to be the functional currency for accounting purposes. The currency translation adjustments reflect translation of the balance sheets valued in local currencies to the U.S. dollar as of the end of each period presented, and translation of revenues and expenses at average exchange rates for each period presented.

Stock Incentive Plans

Stock Incentive Plans	9 Months Ended
	Sep. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Incentive Plans	Stock Incentive Plans On May 11, 2017, GCP filed a Registration Statement on Form S-8 with the SEC for the purpose of registering an additional 8,000,000 shares of Common Stock, par value $0.01 per share, that may be issued under the GCP Applied Technologies Inc. Equity and Incentive Plan (the "Plan"), as amended and restated on February 28, 2017. GCP has provided certain key employees equity awards in the form of stock options, restricted stock units (“RSUs”) and performance-based stock units (“PBUs”) under the Plan. Certain employees and members of the Board of Directors are eligible to receive stock-based compensation, including stock, stock options, RSUs and PBUs. As of September 30, 2017 , approximately 9,098,000 shares of common stock were available for issuance under the Plan. Total cash and non-cash stock-based compensation cost included in "(Loss) income from continuing operations before income taxes" on the Consolidated Statements of Operations is $2.0 million and $1.9 million for the three months ended September 30, 2017 and 2016 , respectively. Total cash and non-cash stock-based compensation cost included in the Consolidated Statements of Operations is $ 7.7 million and $5.3 million for the nine months ended September 30, 2017 and 2016 , respectively. Upon Separation from Grace, previously outstanding stock-based compensation awards granted under Grace’s equity compensation programs were adjusted to reflect the impact of the Separation. To preserve the aggregate intrinsic value of those Grace awards, as measured immediately before and immediately after the Separation, each holder of Grace stock-based compensation awards generally received an adjusted award consisting of either (i) both a stock-based compensation award denominated in Grace equity as it existed subsequent to the Separation and a stock-based compensation award denominated in GCP equity or (ii) solely a stock-based compensation award denominated in the equity of the company at which the person was employed following the Separation. Adjusted awards consisting of stock-based compensation awards denominated in GCP equity are considered issued under the Plan. These adjusted awards generally will be subject to the same vesting conditions and other terms that applied to the original Grace awards before the Separation. Under the Employee Matters Agreement, GCP is obligated to settle all of the stock-based compensation awards denominated in GCP equity, regardless of whether the holders are employees of GCP or Grace. Likewise, Grace is obligated to settle all of the stock-based compensation awards denominated in Grace shares, regardless of whether the holders are employees of GCP or Grace. As a result, GCP recorded a liability for cash-settled awards held by Grace employees. In accordance with certain provisions of the Plan, GCP repurchases shares issued to certain holders of GCP awards in order to fulfill statutory tax withholding requirements for the employee. In the nine months ended September 30, 2017 and 2016 , GCP repurchased approximately 37,000 and 96,000 shares respectively, under these provisions. These purchases are reflected as "Share repurchases" in the Consolidated Statements of Equity (Deficit). Stock Options Stock options are non-qualified and are set at exercise prices not less than 100% of the fair market value on the date of grant (with respect to awards issued before February 28, 2017, fair market value is the average of the high price and low price on the grant date and, with respect to awards issued after February 28, 2017, fair market value is the closing price on the grant date). Stock option awards that relate to Grace stock options originally granted prior to the Separation have a contractual term of five years from the original date of grant. Stock option awards granted post-Separation have a contractual term of seven or ten years from the original date of grant. Generally, stock options vest in substantially equal amounts each year over three years from the date of grant. GCP values stock options using the Black-Scholes option pricing model, which was developed for use in estimating the fair value of traded options. The risk-free rate is based on the U.S. Treasury yield curve published as of the grant date, with maturities approximating the expected term of the options. GCP estimates the expected term of the options according to the simplified method as allowed by ASC 718-20, Awards Classified as Equity, whereby the average between the vesting period and contractual term is used. GCP estimated the expected volatility using an industry peer group. The following summarizes GCP's assumptions for estimating the fair value of stock options granted during 2017 : Assumptions used to calculate expense for stock option Nine Months Ended September 30, 2017 Risk-free interest rate 1.83 - 2.10% Average life of options (years) 5.5 - 6.5 Volatility 31.42 - 31.96% Dividend yield — Average fair value per stock option $9.16 The following table summarizes GCP stock option activity for the nine months ended September 30, 2017 : Stock Option Activity Number Of Weighted Weighted Aggregated Outstanding, December 31, 2016 2,122 $ 16.92 3.57 $ 20,748 Options exercised 493 13.91 Options forfeited/expired/canceled 120 19.64 Options granted 240 26.48 Outstanding, September 30, 2017 1,749 18.90 3.55 20,691 Exercisable September 30, 2017 944 $ 17.81 2.35 $ 12,190 The aggregate intrinsic values in the table above represent the total pre-tax intrinsic value (the difference between GCP's closing stock price on the last trading day of September 2017 and the exercise price, multiplied by the number of in-the-money options) that would have been received by the option holders had all option holders exercised their in-the-money options at period end. The amount changes based on the fair market value of GCP's stock. The intrinsic value of all options exercised in the nine-month period ended September 30, 2017 was $8.3 million . Total unrecognized stock-based compensation expense for stock options outstanding at September 30, 2017 , was $1.1 million and the weighted-average period over which this expense will be recognized is approximately 1.0 years. Restricted Stock Units and Performance Based Stock Units Upon Separation, certain previously outstanding RSUs and PBUs granted under Grace's equity compensation programs prior to the Separation were adjusted, in accordance with the Employee Matters Agreement, such that holders of these original Grace RSUs and PBUs received RSUs denominated in GCP equity. RSUs generally vest over a three year period, with vesting in substantially equal amounts each year over three years and some vesting 100% on the third anniversary of the date of grant. A smaller number of RSUs were designated as sign-on awards and used for purposes of attracting key employees and to cover outstanding awards from a prior employer and vest 100% after two years . GCP’s RSU activity for the nine months ended September 30, 2017 is as follows: RSU Activity Number Of Weighted Outstanding, December 31, 2016 538 $ 17.22 RSUs settled 113 17.23 RSUs forfeited 84 18.26 RSUs granted 95 26.42 RSUs outstanding, September 30, 2017 436 $ 19.02 During the nine months ended September 30, 2017 , GCP distributed 79,917 shares and $0.9 million of cash to settle RSUs. GCP's expectations of future RSU vesting and settlement are as follows: Year Number of Shares Vesting (in thousands) Settled in Cash Settled in Stock 2017 20 —% 100% 2018 179 11% 89% 2019 212 —% 100% 2020 25 —% 100% PBUs and RSUs are recorded at fair value at the date of grant. The common stock-settled awards are considered equity awards, with the stock compensation expense being determined based on GCP’s stock price on the grant date. The cash settled awards are considered liability awards, with the liability being remeasured each reporting period based on GCP’s then current stock price. During the nine months ended September 30, 2017 , GCP granted 165,974 PBUs under the Plan to Company employees. These awards vest upon certification by the Board's Compensation Committee that the applicable performance criteria have been satisfied (such certification would likely occur in February 2020 ), are subject to the employees' continued employment through the vesting date, and have a weighted average grant date fair value of $26.48 . During the nine months ended September 30, 2017 , 13,257 of these awards were forfeited. PBUs that were granted during the year ended December 31, 2016 under the Plan to Company employees remain outstanding as of September 30, 2017 . These awards vest upon certification by the Board's Compensation Committee that the applicable performance criteria have been satisfied (such certification would likely occur in February 2019 ), are subject to the employees' continued employment through the vesting date, and have a weighted average grant date fair value of $17.04 . GCP anticipates that 100% of the PBUs will be settled in GCP common stock upon vesting. During the nine months ended September 30, 2017 , 35,505 of these awards were forfeited. The performance criteria for PBUs granted in 2017 is a three -year cumulative adjusted diluted earnings per share metric that is modified, up or down, based on the Company's relative total shareholder return as against the Russell 3000 Index. The number of shares subject to a 2017 PBU award that ultimately vest, if any, is based on Company performance against these metrics, and can range from 0% to 200% of the target number of shares granted to the employee. The awards will become vested, if at all, no later than March 15, 2020 , once actual performance for the 2017 - 2019 performance period is certified by the Board's Compensation Committee. PBUs are remeasured each reporting period based on the expected payout of the award, which may range from 0% to 200% of the targets for such awards; therefore, these portions of the awards are subject to volatility until the payout is finally determined at the end of the applicable performance period. As of September 30, 2017 , $6.4 million of total unrecognized compensation expense related to the RSU and PBU awards is expected to be recognized over the remaining weighted-average service period of 1.4 years.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following table shows a reconciliation of the numerators and denominators used in calculating basic and diluted (loss) earnings per share: Three Months Ended September 30, Nine Months Ended September 30, (In millions, except per share amounts) 2017 2016 2017 2016 Numerators Net (loss) income from continuing operations attributable to GCP shareholders $ (18.1 ) $ 10.9 $ (41.8 ) $ 33.2 Income from discontinued operations, net of income taxes $ 677.3 $ 10.4 $ 679.4 $ 36.2 Net income attributable to GCP shareholders $ 659.2 $ 21.3 $ 637.6 $ 69.4 Denominators Weighted average common shares—basic calculation 71.6 71.0 71.2 70.8 Dilutive effect of employee stock awards (1) — 1.2 — 0.8 Weighted average common shares—diluted calculation 71.6 72.2 71.2 71.6 Basic (loss) earnings per share Net (loss) income from continuing operations attributable to GCP shareholders $ (0.25 ) $ 0.15 $ (0.59 ) $ 0.47 Income from discontinued operations, net of income taxes $ 9.46 $ 0.15 $ 9.54 $ 0.51 Net income attributable to GCP shareholders (2) $ 9.21 $ 0.30 $ 8.96 $ 0.98 Diluted (loss) earnings per share Net (loss) income from continuing operations attributable to GCP shareholders $ (0.25 ) $ 0.15 $ (0.59 ) $ 0.46 Income from discontinued operations, net of income taxes $ 9.46 $ 0.14 $ 9.54 $ 0.51 Net income attributable to GCP shareholders (2) $ 9.21 $ 0.30 $ 8.96 $ 0.97 ______________________________ (1) Dilutive effect only applicable to periods where there is net income from continuing operations. (2) Amounts may not sum due to rounding. For 2016, the computation of basic and diluted earnings per common share is calculated assuming the number of shares of GCP common stock outstanding on February 3, 2016 had been outstanding at the beginning of the period. There were approximately 0.1 million anti-dilutive options and no anti-dilutive RSUs outstanding on a weighted-average basis for the three and nine months ended September 30, 2017 . There were approximately 0.2 million anti-dilutive options and 0.1 million anti-dilutive RSUs outstanding on a weighted average basis for the nine months ended September 30, 2016 . There were no anti-dilutive options and or anti-dilutive RSUs outstanding on a weighted average basis for the three months ended September 30, 2016 . During the nine months ended September 30, 2017 and 2016, GCP repurchased approximately 37,000 shares and 96,000 shares of Company common stock for $1.0 million and $1.8 million , respectively, in connection with its equity compensation programs.

Related Party Transactions and

Related Party Transactions and Transactions with Grace	9 Months Ended
	Sep. 30, 2017
Related Party Transactions [Abstract]
Related Party Transactions and Transactions with Grace	Related Party Transactions and Transactions with Grace Related Parties All contracts with related parties are at rates and terms that GCP believes are comparable with those that could be entered into with independent third parties. Subsequent to the Separation, transactions with Grace represent third-party transactions. Allocation of General Corporate Expenses Prior to the Separation, the financial statements included expense allocations for certain functions provided by Grace as well as other Grace employees not solely dedicated to GCP, including, but not limited to, general corporate expenses related to finance, legal, information technology, human resources, communications, ethics and compliance, shared services, employee benefits and incentives and stock-based compensation. These expenses were allocated to GCP on the basis of direct usage when identifiable, with the remainder allocated on the basis of revenue, headcount or other measures. Between January 1, 2016 and the Separation, GCP was allocated $ 2.0 million of general corporate expense, which is primarily included within "Selling, general and administrative expenses" in the accompanying Statement of Operations for the nine months ended September 30, 2016 . Transition Services Agreement In connection with the Separation, the Company entered into a transition services agreement pursuant to which GCP and Grace provided various services to each other on a temporary, transitional basis. The services provided by Grace to GCP included information technology, treasury, tax administration, accounting, financial reporting, human resources and other services. Following the Separation, Grace provided some of these services on a transitional basis, generally for a period of up to 18 months . As of the third quarter 2017, these transitional services are substantially complete. Tax Sharing Agreement The Tax Sharing Agreement governs the parties’ respective rights, responsibilities and obligations with respect to tax liabilities and benefits, tax attributes, the preparation and filing of tax returns, the control of audits and other tax proceedings, and other matters regarding taxes. In general, and subject to the terms of the Tax Sharing Agreement, GCP is responsible for all U.S. federal, state and foreign taxes (and any related interest, penalties or audit adjustments) reportable on a GCP separate return (a return that does not include Grace or any of its subsidiaries); and Grace is responsible for all U.S. federal, state and foreign income taxes (and any related interest, penalties or audit adjustments) reportable on a consolidated, combined or unitary return that includes Grace or any of its subsidiaries and GCP or any of its subsidiaries up to the Separation date. As of the balance sheet date, GCP has included $10.3 million of indemnified receivables in "Other assets" and $2.6 million of indemnified payables in "Other current liabilities." In addition, the Tax Sharing Agreement imposes certain restrictions on GCP and its subsidiaries (including restrictions on share issuances, business combinations, sales of assets and similar transactions) that are designed to preserve the qualification of the Distribution, together with certain related transactions, under Section 355 and certain other relevant provisions of the Code. The Tax Sharing Agreement provides special rules that allocate tax liabilities in the event the Distribution, together with certain related transactions, does not so qualify. In general, under the Tax Sharing Agreement, each party is expected to be responsible for any taxes imposed on, and certain related amounts payable by, GCP or Grace that arise from the failure of the Distribution and certain related transactions, to qualify under Section 355 and certain other relevant provisions of the Code, to the extent that the failure to so qualify is attributable to actions, events or transactions relating to such party’s respective stock, assets or business, or a breach of the relevant representations or covenants made by such party in the Tax Sharing Agreement. Parent Company Equity Net transfers to parent are included within net parent investment on the Consolidated Statements of Equity (Deficit). The components of the net transfers to parent as of September 30, 2016 are as follows: (In millions) 2016 Cash pooling and general financing activities $ (685.1 ) GCP expenses funded by parent 6.6 Corporate costs allocations 2.0 Provision for income taxes 4.3 Total net transfers to parent (672.2 ) Other, net (86.5 ) Transfers to parent, net, per Consolidated Statement of Cash Flows $ (758.7 ) In the nine months ended September 30, 2017 , there were no adjustments to parent company equity. In 2016, "Other, net" includes the non-cash transfer from parent of approximately $44 million of net pension liabilities, approximately $23 million of fixed assets and the non-cash transfer of approximately $36 million of related-party debt, deferred tax items and other items. GCP used proceeds from the Notes and Credit Facilities to fund a distribution to Grace in an amount of $750.0 million related to the Separation. This distribution is reflected as a component of transfers to parent in the table above.

Operating Segment Information

Operating Segment Information	9 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Operating Segment Information	Operating Segment Information GCP is engaged in the production and sale of specialty construction chemicals and specialty building materials through two operating segments. Specialty Construction Chemicals manufactures and markets concrete admixtures and cement additives. Specialty Building Materials manufactures and markets sheet and liquid membrane systems that protect structures from water, air and vapor penetration, fireproofing, and other products designed to protect the building envelope. The table below presents information related to GCP's operating segments. Only those corporate expenses directly related to the operating segments are allocated for reporting purposes. GCP excludes certain functional costs, impacts of foreign exchange (related primarily to Venezuela for periods up through the deconsolidation date of July 3, 2017, as discussed in Note 1) and other corporate costs such as certain performance-based incentive compensation and public company costs from segment operating income. GCP also excludes certain ongoing defined benefit pension costs recognized quarterly, which include service and interest costs, the effect of expected returns on plan assets and amortization of prior service costs/credits, from the calculation of segment operating income. GCP believes that the exclusion of certain corporate costs and pension costs provides a better indicator of its operating segment performance as such costs are not managed at an operating segment level. Operating Segment Data Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Net Sales Specialty Construction Chemicals $ 156.2 $ 162.8 $ 449.1 $ 466.6 Specialty Building Materials 126.2 100.6 345.8 318.5 Total net sales $ 282.4 $ 263.4 $ 794.9 $ 785.1 Segment Operating Income Specialty Construction Chemicals $ 15.7 $ 23.2 $ 44.5 $ 53.7 Specialty Building Materials 30.1 25.6 80.6 88.9 Total segment operating income $ 45.8 $ 48.8 $ 125.1 $ 142.6 Reconciliation of Operating Segment Data to Financial Statements Total segment operating income for the three and nine months ended September 30, 2017 and 2016 , is reconciled below to "(Loss) income from continuing operations before income taxes" presented in the accompanying Consolidated Statements of Operations: Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Total segment operating income $ 45.8 $ 48.8 $ 125.1 $ 142.6 Corporate costs (1) (7.5 ) (9.0 ) (28.9 ) (29.1 ) Certain pension costs (2.1 ) (1.8 ) (7.0 ) (5.4 ) Loss on sale of product line — — (2.1 ) — Currency and other financial losses in Venezuela (36.7 ) — (39.1 ) — Litigation settlement (4.0 ) — (4.0 ) — Repositioning expenses (1.1 ) (5.3 ) (6.8 ) (14.3 ) Restructuring expenses and asset impairments (2.1 ) (0.4 ) (13.0 ) (1.4 ) Pension MTM adjustment and other related costs, net (3.0 ) — (2.9 ) (2.7 ) Gain on termination and curtailment of pension and other postretirement plans 0.8 0.2 5.9 2.6 Third-party and other acquisition-related costs (2.0 ) (0.3 ) (5.0 ) (0.3 ) Amortization of acquired inventory fair value adjustment (0.2 ) — (2.9 ) — Tax indemnification adjustments — — (2.4 ) — Net income attributable to noncontrolling interests 0.1 0.2 0.2 0.9 Other financing costs (6.0 ) (1.2 ) (6.0 ) (1.2 ) Interest expense, net (14.5 ) (17.6 ) (49.0 ) (47.8 ) (Loss) income from continuing operations before income taxes $ (32.5 ) $ 13.6 $ (37.9 ) $ 43.9 _______________________________ (1) Corporate costs include $5.4 million and $7.0 million of allocated costs in the nine months ended September 30, 2017 and 2016 , respectively, and $2.6 million of allocated costs in the three months ended September 30, 2016 that were previously reported within the Darex operating segment. Such costs did not qualify to be reclassified to discontinued operations. For the three months ended September 30, 2017, the Company began allocating these costs to its remaining operating segments. Geographic Area Data The table below presents information related to the geographic areas in which GCP operates. Sales are attributed to geographic areas based on customer location. Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Net Sales United States $ 132.5 $ 119.6 $ 374.2 $ 353.1 Canada and Puerto Rico 9.0 9.0 21.8 24.9 Total North America 141.5 128.6 396.0 378.0 Europe Middle East Africa 67.0 55.3 178.9 173.9 Asia Pacific 58.0 61.3 168.4 180.9 Latin America 15.9 18.2 51.6 52.3 Total $ 282.4 $ 263.4 $ 794.9 $ 785.1

Discontinued Operations

Discontinued Operations	9 Months Ended
	Sep. 30, 2017
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	Discontinued Operations On July 3, 2017, the Company completed the sale of Darex to Henkel for $1.06 billion in cash, subject to customary closing adjustments (the “Disposition”). In accordance with applicable accounting guidance, the assets and liabilities related to Darex have been reclassified and reflected as "held for sale" on the Consolidated Balance Sheet as of December 31, 2016. In addition, Darex results have been reclassified and reflected as "discontinued operations" on the Consolidated Statements of Operations and Consolidated Statements of Cash Flows for all periods presented. The agreement with Henkel governing the Disposition (the “Amended Purchase Agreement”) provides for a series of delayed closings that will take place in certain non-U.S. jurisdictions, including Argentina, China, Colombia, Indonesia, Peru and Venezuela. The delayed closings will implement the legal transfer of the Darex business in the delayed closing jurisdictions in accordance with local law over the following four to 27 months. Up to the time of the delayed closings for these countries, the results of the operations of the Darex business in the delayed close countries are reported as “Income (loss) from discontinued operations, net of income taxes” in the Consolidated Statements of Operations, and reflect an economic benefit payable to or recoverable from Henkel, as applicable for each reporting period, per the Amended Purchase Agreement. The assets and liabilities of the Darex business in the delayed close countries are categorized as “Assets held for sale” or “Liabilities held for sale” in the accompanying Consolidated Balance Sheet as of September 30, 2017. In connection with the Disposition, the Company and Henkel also entered into a Transition Services Agreement pursuant to which Henkel and the Company will provide various services to each other in connection with the transition of the Darex business to Henkel. The Company and Henkel expect to perform these services, which relate to real estate, information technology, accounts payable, payroll and other financial functions and administrative services, for various periods up to 24 months following the closing date. The charges for such services generally allow the servicing party to recover all out-of-pocket costs and expenses. Additionally, in connection with the Disposition, the Company and Henkel entered into a Master Tolling Agreement, whereby Henkel will operate certain equipment at facilities being sold in order to manufacture and prepare for shipping certain products related to product lines that the Company continues to own. The Company and Henkel expect these services to be provided for a period of 24 months following the closing date, which can be further extended. Under the Amended Purchase Agreement, GCP is required to indemnify Henkel for certain possible future tax liabilities. GCP has recorded an indemnification payable of $5.7 million in this regard as a result of the Disposition. GCP recognized a pre-tax gain on the sale of Darex of approximately $883.7 million during the third quarter of 2017. The calculation of the pre-tax gain excludes deferral of $68.7 million of consideration related to the delayed closings, which was received on the closing date. Deferred consideration is recorded in “Other current liabilities” and “Other liabilities” on the Consolidated Balance Sheet as of September 30, 2017. Refer to the table below for a reconciliation of the gain recorded on the sale of Darex at the closing date. (In millions) Net proceeds included in gain recognized in third quarter of 2017 $ 1,000.2 Less: Transaction costs 15.9 Less: Net assets derecognized in third quarter of 2017 100.6 Gain recognized in third quarter of 2017 before income taxes 883.7 Less: Tax effect of gain recognized in third quarter of 2017 200.0 Gain recognized in third quarter of 2017 after income taxes $ 683.7 In connection with the Disposition and related tax gain, as noted above, the Company has recorded tax expense of approximately $200 million within discontinued operations. The tax consequences of the Disposition are complex and the calculation of the provision is based on management’s best estimate using all readily accessible information. Management is in the process of completing further analysis related to the stock basis, earnings and profits, tax pools, transaction costs and other related components associated with the Disposition. Based on the overall complexity of the calculation, management believes that there is a reasonable possibility that differences between the estimated tax provision and actual outcome may result within the next 12 months, which could have a material impact on the Company's results of operations. As a result of the Disposition, GCP recorded an unrecognized tax benefit of $31.2 million , which is reflected in the tax effect of the gain and within income tax expense in discontinued operations for the three and nine months ended September 30, 2017. "Income from discontinued operations, net of income taxes" in the accompanying Statements of Operations is comprised of the following: Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Net sales $ 9.1 $ 79.1 $ 156.9 $ 237.8 Cost of goods sold 6.0 51.7 104.6 152.2 Selling, general and administrative expenses 6.6 8.0 40.1 24.1 Research and development expenses 0.1 1.2 2.3 3.5 Restructuring expenses 0.4 — 6.9 — Gain on sale of business (883.7 ) — (883.7 ) — Other non-operating expenses, net 2.4 0.7 7.5 1.8 Provision for income taxes (200.0 ) (7.1 ) (199.7 ) (20.0 ) Less: Net income attributable to noncontrolling interests — — (0.1 ) — Income from discontinued operations, net of income taxes $ 677.3 $ 10.4 $ 679.4 $ 36.2 The carrying amounts of the major classes of assets and liabilities of Darex classified as "held for sale" as of September 30, 2017 and December 31, 2016 consist of the following: (In millions) September 30, 2017 December 31, 2016 Cash and cash equivalents $ — $ 16.3 Trade accounts receivable 7.9 50.5 Inventories 7.9 32.3 Other current assets 1.0 8.9 Current assets held for sale 16.8 108.0 Properties and equipment, net 1.9 39.6 Goodwill — 4.4 Technology and other intangible assets, net — 0.4 Deferred income taxes — 6.4 Other assets 0.6 4.6 Noncurrent assets held for sale 2.5 55.4 Accounts payable 6.8 26.7 Other current liabilities 1.3 21.5 Current liabilities held for sale 8.1 48.2 Deferred income taxes — 2.3 Underfunded and unfunded defined benefit pension plans 0.3 14.8 Other liabilities — 3.8 Noncurrent liabilities held for sale $ 0.3 $ 20.9

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2017
Business Combinations [Abstract]
Acquisitions	Acquisitions Acquisition of Stirling Lloyd Plc On May 17, 2017, GCP acquired 100% of the share capital of Stirling Lloyd Plc ("Stirling Lloyd"), a UK-based global supplier of high-performance liquid waterproofing and coatings products, for total consideration of $91.1 million , net of $16.1 million of cash acquired. The Company believes that the addition of Stirling Lloyd and its products, which are used for the protection of infrastructure and buildings, opens new growth opportunities by offering additional selling channels in targeting specialized end-market applications. The Company has accounted for the acquisition as a business combination in accordance with ASC 805, Business Combinations ("ASC 805") , and has included Stirling Lloyd within the SBM operating and reportable segment. In applying the provisions of ASC 805 and determining that Stirling Lloyd represents a business, the Company elected to early adopt and apply ASU 2017-01 (refer to Note 1). Under ASU 2017-01, the Company first assessed whether all of the fair value of the acquired Stirling Lloyd gross assets is concentrated in a single identifiable asset or group of identifiable assets. If that concentration existed, Stirling Lloyd would not be considered a business. The Company concluded that there was not such a concentration, as the fair value of the acquired gross assets is distributed between various intangible and tangible assets. The Company has allocated the acquisition purchase price to the tangible net assets and identifiable intangible assets acquired based on their estimated fair values at the acquisition date and recorded the excess as goodwill. The Company recognized $59.6 million of goodwill, which is attributable to the revenue growth and operating synergies that GCP expects to realize from this acquisition. During the quarter ended September 30, 2017, the Company finalized its purchase price allocation and recorded $0.6 million decrease to goodwill, primarily related to final settlement of assets and liabilities transferred between the seller and the buyer. The following table presents the aggregate purchase price allocation as of September 30, 2017. (In millions) Net Assets Acquired Accounts receivable, net $ 6.8 Other current assets 3.1 Inventories 4.2 Properties and equipment, net 3.4 Goodwill 59.6 Intangible assets 26.9 Accounts payable (2.9 ) Other current liabilities (4.2 ) Other liabilities (5.8 ) Net assets acquired $ 91.1 The table below presents the intangible assets acquired as part of the acquisition of Stirling Lloyd and the periods over which they will be amortized. Amount (In millions) Weighted-Average Amortization Period (in years) Customer Lists $ 15.0 10 Technology 9.8 11 Trademarks 2.1 10 Total $ 26.9

Subsequent Event

Subsequent Event	9 Months Ended
	Sep. 30, 2017
Subsequent Events [Abstract]
Subsequent Event	Subsequent Event On October 31, 2017, GCP acquired 100% of the stock of Ductilcrete Technologies ("Ductilcrete"), a technology leader for concrete flooring systems, for approximately $32 million in cash, subject to normal and customary purchase price adjustments. The business will be included within the Company's SCC operating segment. Due to the timing of the acquisition, the Company has not yet finalized the purchase price allocation in accordance with ASC 805.

Basis of Presentation and Sum24

Basis of Presentation and Summary of Significant Accounting and Financial Reporting Policies (Policies)	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying Consolidated Financial Statements are presented on a consolidated basis and include all of the accounts and operations of GCP and its majority-owned subsidiaries, except as noted below with respect to the Company's Venezuela subsidiary. The financial statements reflect the financial position, results of operations and cash flows of GCP in accordance with generally accepted accounting principles in the United States of America ("GAAP") and with the instructions to Form 10-Q and Article 10 of SEC Regulation S-X for interim financial information. The interim 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 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 nine-month period ended September 30, 2017 are not necessarily indicative of the results of operations for the year ending December 31, 2017 .
Discontinued Operations	Discontinued Operations As noted above, on July 3, 2017, the Company completed the sale of Darex to Henkel. In conjunction with this transaction and applicable GAAP, the assets and liabilities related to Darex have been reclassified and reflected as "held for sale" on the Consolidated Balance Sheet as of December 31, 2016. As discussed further in Note 14, the assets and liabilities of the Darex business in certain delayed close countries are categorized as “Assets held for sale” or “Liabilities held for sale” in the accompanying Consolidated Balance Sheet as of September 30, 2017. Additionally, Darex has been reclassified and reflected as "discontinued operations" on the Consolidated Statements of Operations and Consolidated Statements of Cash Flows for all periods presented. GCP recognized a pre-tax gain on the sale of Darex of approximately $883.7 million during the third quarter of 2017. The calculation of the pre-tax gain excludes deferral of $68.7 million of consideration related to the delayed closings, which was received on the closing date. Deferred consideration is recorded in “Other current liabilities” and “Other liabilities” on the Consolidated Balance Sheet as of September 30, 2017. Unless otherwise noted, the information throughout the Notes to the Consolidated Financial Statements pertains only to the continuing operations of GCP. Refer to Note 14 for further discussion of the sale of Darex.
Principles of Combination	Deconsolidation of Venezuelan Operations Prior to July 3, 2017, the Company included the results of its Venezuelan operations (“GCP Venezuela”) in the Consolidated Financial Statements using the consolidation method of accounting. Venezuelan exchange control regulations have resulted in an other-than-temporary lack of exchangeability between the Venezuelan bolivar and U.S. dollar, and have restricted GCP Venezuela’s ability to pay dividends and meet obligations denominated in U.S. dollars. These exchange regulations, combined with other recently adopted regulations, have constrained availability of raw materials and have significantly limited GCP Venezuela’s ability to maintain normal production. As a result of these conditions, combined with the loss of scale in Venezuela resulting from the sale of the Company’s Darex-related operations and assets in Venezuela, GCP has deconsolidated its Venezuelan operations as of July 3, 2017 in accordance with Financial Accounting Standards Board ("FASB") Accounting Standards Codification ("ASC") 810, Consolidation . Subsequent to this date, the Company began accounting for GCP Venezuela using the cost method of accounting. This change resulted in a third quarter 2017 pre-tax charge of $36.7 million ( $23.8 million net of tax), which is reflected in “Loss in Venezuela” in the accompanying Statement of Operations, primarily related to the recognition of $33.4 million of unfavorable cumulative translation adjustments associated with the Venezuelan business. In the third quarter of 2017, GCP recorded an out-period-adjustment to correct the misclassification of a $3.4 million foreign exchange remeasurement loss that was incorrectly included within discontinued operations in the second quarter of 2017. The impact of this correction, of which $2.9 million is reflected in "Loss on Venezuela" and $0.5 million is reflected in "Other income, net" on the Consolidated Statement of Operations, resulted in an increase in "Loss from continuing operations." There was no tax impact associated with this adjustment. There is no impact to the Consolidated Statement of Operations for the nine-month period ended September 30, 2017. GCP has assessed the impact of this error and concluded that the amount was not material to any prior-period financial statements and the impact of correcting this error in the current period is not material. In periods subsequent to July 3, 2017, the Company’s financial results will not include the operating results of GCP Venezuela. The Company will record cash and recognize income from its Venezuelan operations in the consolidated financial statements to the extent GCP is paid for inventory sold to or dividends received from GCP Venezuela. The remaining investment on the Company's Consolidated Balance Sheet as of September 30, 2017 is immaterial.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with 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. GCP's accounting measurements that are most affected by management's estimates of future events are disclosed in its 2016 Annual Report on Form 10-K; there have been no significant changes to management's assumptions and estimates underlying those measurements as reported in these interim financial statements.
Reclassifications	Reclassifications Certain amounts in prior period financial statements have been reclassified to conform to the current period presentation. Such reclassifications have not materially affected previously reported amounts.
Income Tax	Income Tax As a global enterprise, GCP is subject to a complex array of tax regulations and must make assessments of applicable tax law and judgments in estimating its ultimate income tax liability. Refer to Note 4 for details regarding estimates used in accounting for income tax matters including unrecognized tax benefits.
Stock-Based Compensation Expense	Stock-Based Compensation Expense Prior to the Separation, GCP was allocated stock-based compensation expense from Grace related to GCP employees receiving awards denominated in Grace equity instruments. In accordance with an employee matters agreement entered into between Grace and GCP on January 27, 2016 in connection with the Separation (the "Employee Matters Agreement"), previously outstanding stock-based compensation awards granted under Grace's equity compensation programs prior to the Separation and held by certain executives and employees of GCP and Grace were adjusted to reflect the impact of the Separation on these awards. To preserve the aggregate intrinsic value of these stock-based compensation awards, as measured immediately before and immediately after the Separation, each holder of Grace stock-based compensation awards generally received an adjusted award consisting of either (i) both a stock-based compensation award denominated in Grace equity as it existed subsequent to the Separation and a stock-based compensation award denominated in GCP equity or (ii) solely a stock-based compensation award denominated in the equity of the company at which the person was employed following the Separation. In the Separation, the determination as to which type of adjustment applied to a holder’s previously outstanding Grace award was based upon the type of stock-based compensation award that was to be adjusted and the date on which the award was originally granted under the Grace equity compensation programs prior to the Separation. Under the Employee Matters Agreement, GCP retains certain obligations related to all stock- and cash-settled stock-based compensation awards denominated in GCP equity, regardless of whether the holder is a GCP or Grace employee. Following the Separation, the Company records stock-based compensation expense for equity awards in accordance with authoritative accounting guidance.
Currency Translation	Currency Translation Assets and liabilities of foreign subsidiaries (other than those located in countries with highly inflationary economies) are translated into U.S. dollars at current exchange rates, while revenues, costs and expenses are translated at average exchange rates during each reporting period. The resulting currency translation adjustments are included in accumulated other comprehensive income or loss in the Consolidated Balance Sheets. The financial statements of subsidiaries located in countries with highly inflationary economies are remeasured as if the functional currency were the U.S. dollar; the remeasurement creates translation adjustments that are reflected in net income in the Consolidated Statements of Operations.
Recently Issued/Adopted Accounting Standards	Recently Issued Accounting Standards Derivatives and Hedging In August 2017, the FASB issued Accounting Standards Update ("ASU") 2017-12, Derivatives and Hedging (Topic 815). The amendments in this update improve the financial reporting of hedging relationships to better portray the economic results of an entity's risk management activities in its financial statements by expanding and refining hedge accounting for both nonfinancial and financial risk components and aligning the recognition and presentation of the effects of the hedging instrument and the hedged item in the financial statements. The standard is effective for the Company as of January 1, 2019, and early adoption is permitted. GCP is currently evaluating the potential impact on its Consolidated Financial Statements and related disclosures, but does not expect the adoption of this standard will have a material effect on its Consolidated Financial Statements. Stock Compensation In May 2017, the FASB issued ASU 2017-09, Compensation—Stock Compensation (Topic 718), which provides guidance about which changes to the terms or conditions of a share-based payment award require an entity to apply modification accounting in Topic 718. The standard is effective for the Company on January 1, 2018, with early adoption permitted, including adoption in any interim period, for public business entities for reporting periods for which financial statements have not yet been issued. The amendments in this update should be applied prospectively to an award modified on or after the adoption date, and, therefore, GCP will consider the provisions of this update in conjunction with awards issued on or after January 1, 2018, as applicable. Goodwill In January 2017, the FASB issued ASU 2017-04, Intangibles—Goodwill and Other (Topic 350) . This ASU 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, which eliminates Step 2 from the goodwill impairment test. The standard is effective for the Company for annual or any interim goodwill impairment tests beginning on or after January 1, 2020. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. Revenue from Contracts with Customers In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606) . 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 revised 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. GCP will adopt the standard beginning January 1, 2018. GCP has preliminarily determined that it will adopt Topic 606 through a cumulative adjustment to retained earnings, as opposed to retrospectively adjusting prior periods, and continues to progress in its evaluation of the potential impact of the standard on its Consolidated Financial Statements and related disclosures. To date, a multi-disciplinary project team has analyzed certain of the Company's sales contracts and practices as compared to the new guidance and has begun to develop implementation steps to address the initial impact of adoption, including ongoing policy and process changes. In addition to the expanded disclosures regarding revenue, the guidance may affect the timing of revenue recognition for certain of the Company’s arrangements that involve multiple performance obligations, as well as arrangements containing variable consideration. Leases In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which 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. GCP is currently evaluating the potential impact on its Consolidated Financial Statements and related disclosures. Other new pronouncements issued but not effective until after September 30, 2017 are not expected to have a material impact on the Company's financial position, results of operations or liquidity. Recently Adopted Accounting Standards Business Combinations In January 2017, the FASB issued ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business , which clarifies the definition of a business when evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The update provides that when substantially all the fair value of the assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets, the transaction does not involve a business. The standard is effective for the Company on January 1, 2018, with early application permitted for certain transactions. GCP elected to early adopt the provisions of this update in the second quarter of 2017 in conjunction with its acquisition of Stirling Lloyd Plc (refer to Note 15). Pension and Other Postretirement Benefit Costs In March 2017, the FASB issued ASU 2017-07, Compensation—Retirement Benefits (Topic 715) : Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost, which changes certain presentation and disclosure requirements for employers that sponsor defined benefit pension and other postretirement benefit plans. The amendments in this ASU require entities to (1) report the service cost component of net periodic pension/postretirement benefit cost in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period; (2) capitalize only the service cost component of net periodic pension/postretirement benefit cost (when applicable); and (3) present other components of net periodic pension/postretirement benefit cost separately from the service cost component and outside a subtotal of income from operations (if applicable). The standard is effective for the Company on January 1, 2018, with early adoption permitted as of January 1, 2017. GCP elected to early adopt this standard in the first quarter of 2017 and has reflected only the service cost component of net periodic pension/postretirement benefit cost in "Cost of goods sold" and presented the other components of net periodic pension/postretirement benefit cost in "Other income, net," within the Consolidated Statements of Operations. In accordance with the standard, GCP utilized prior period footnote disclosures as a practical expedient to apply these retrospective presentation requirements and will prospectively apply the capitalization requirements. GCP's adoption of this standard did not have a material effect on the accompanying Consolidated Financial Statements. Inventory In July 2015, the FASB issued ASU 2015-11, Simplifying the Measurement of Inventory . The update requires that inventory be measured at the lower of cost or net realizable value for entities using first-in, first-out ("FIFO") 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. GCP adopted this standard for the 2017 first quarter and there were no material effects on the accompanying Consolidated Financial Statements.

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Sep. 30, 2017
Inventory Disclosure [Abstract]
Schedule of Inventories	Inventories presented on GCP's Consolidated Balance Sheets consisted of the following: (In millions) September 30, December 31, Raw materials $ 40.2 $ 35.7 In process 4.0 3.6 Finished products and other 64.2 50.0 Total inventories $ 108.4 $ 89.3

Debt and Other Financial Inst26

Debt and Other Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
Components of Debt	Components of Debt (In millions) September 30, December 31, 9.5% Senior Notes due 2023, net of unamortized debt issuance costs of $6.6 at September 30, 2017 (2016 — $7.3) $ 518.4 $ 517.7 Term Loan due 2022, net of unamortized discount of $2.4M and unamortized debt issuance costs of $4.3M at December 31, 2016 (1) — 266.2 Revolving credit facility due 2021 (2) — 25.0 Other borrowings (3) 25.7 22.0 Total debt 544.1 830.9 Less debt payable within one year 23.8 47.9 Debt payable after one year $ 520.3 $ 783.0 Weighted average interest rates on total debt 9.4 % 7.5 % __________________________ (1) GCP repaid the outstanding principal balance and accrued interest on the Term Loan in July 2017. Refer below to "Credit Agreement" disclosure. (2) Interest at LIBOR + 200 bps at September 30, 2017 . (3) Represents borrowings under various lines of credit and other borrowings, primarily by non-U.S. subsidiaries.
Principal Maturities of Debt Outstanding	The principal maturities of debt outstanding (net of unamortized discounts and debt issuance costs) at September 30, 2017 , were as follows: (In millions) 2017 $ 23.4 2018 0.9 2019 0.9 2020 0.5 2021 — Thereafter 518.4 Total debt $ 544.1
Carrying Amounts and Fair Values of Debt Instruments	At September 30, 2017 , the carrying amounts and fair values of GCP's debt were as follows: September 30, 2017 December 31, 2016 (In millions) Carrying Amount Fair Value Carrying Amount Fair Value 9.5% Senior Notes due 2023 $ 518.4 $ 592.6 $ 517.7 $ 603.1 Term Loan due 2022 — — 266.2 274.6 Revolving credit facility due 2021 — — 25.0 25.0 Other borrowings 25.7 25.7 22.0 22.0 Total debt $ 544.1 $ 618.3 $ 830.9 $ 924.7

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Schedule of Effective Income Tax Rate Reconciliation	The difference between the provision for income taxes at the U.S. federal income tax rate of 35% and GCP’s overall income tax rate is summarized below. Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Income tax (benefit) expense at U.S. federal income tax rate $ (11.4 ) $ 4.8 $ (13.3 ) $ 15.4 Change in income tax (benefit) expense resulting from: Valuation allowance — — 13.9 — Tax on undistributed foreign earnings (2.9 ) — 3.6 — Effect of tax rates in foreign jurisdictions (0.1 ) (0.5 ) 0.1 (3.9 ) Permanent items and other (0.1 ) (1.8 ) (0.6 ) (1.7 ) Income tax (benefit) expense $ (14.5 ) $ 2.5 $ 3.7 $ 9.8

Pension Plans and Other Postr28

Pension Plans and Other Postretirement Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2017
Pension and Other Postretirement Benefits Cost (Reversal of Cost) [Abstract]
Net Funded Status of Over-Funded, Underfunded, and Unfunded Pension Plans	The following table presents the funded status of GCP's overfunded, underfunded and unfunded defined pension plans from continuing operations: (In millions) September 30, December 31, Overfunded defined benefit pension plans $ 22.1 $ 21.2 Underfunded defined benefit pension plans (57.9 ) (55.6 ) Unfunded defined benefit pension plans (27.7 ) (27.6 ) Total underfunded and unfunded defined benefit pension plans (85.6 ) (83.2 ) Pension liabilities included in other current liabilities (1.0 ) (0.4 ) Net funded status $ (64.5 ) $ (62.4 )
Components of Net Periodic Benefit Cost (Income)	Components of Net Periodic Benefit Cost (Income) Three Months Ended September 30, 2017 2016 Pension Pension (In millions) U.S. Non-U.S. Other Post U.S. Non-U.S. Other Post Service cost $ 1.6 $ 0.8 $ — $ 1.6 $ 0.8 $ — Interest cost 1.3 1.4 — 1.1 1.9 — Expected return on plan assets (1.4 ) (1.6 ) — (1.2 ) (2.1 ) — Amortization of net deferred actuarial loss — — — — — 0.1 Mark-to-market adjustment 1.2 1.7 — — — — Gain on curtailments, settlements and terminations (2.8 ) (14.3 ) — — (0.2 ) — Net periodic benefit (income) cost $ (0.1 ) $ (12.0 ) $ — $ 1.5 $ 0.4 $ 0.1 Less: Discontinued operations (income) cost (2.1 ) (14.4 ) — — 0.3 — Net periodic benefit cost from continuing operations $ 2.0 $ 2.4 $ — $ 1.5 $ 0.1 $ 0.1 Nine Months Ended September 30, 2017 2016 Pension Pension (In millions) U.S. Non-U.S. Other Post U.S. Non-U.S. Other Post Service cost $ 5.3 $ 3.0 $ — $ 4.6 $ 2.5 $ — Interest cost 4.2 4.3 — 3.5 6.0 — Expected return on plan assets (4.2 ) (5.1 ) — (3.7 ) (6.6 ) — Amortization of prior service credit — — — — — (0.1 ) Amortization of net deferred actuarial loss — — — — — 0.1 Mark-to-market adjustment 1.2 1.6 — — — — Gain on termination and curtailment of pension and other postretirement plans (8.4 ) (14.3 ) — — (1.6 ) (1.0 ) Net periodic benefit (income) cost $ (1.9 ) $ (10.5 ) $ — $ 4.4 $ 0.3 $ (1.0 ) Less: Discontinued operations (income) cost (2.6 ) (13.9 ) — — 0.9 — Net periodic benefit cost (income) from continuing operations $ 0.7 $ 3.4 $ — $ 4.4 $ (0.6 ) $ (1.0 )

Other Balance Sheet Accounts (T

Other Balance Sheet Accounts (Tables)	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Other Current Assets	(In millions) September 30, December 31, Other Current Assets: Non-trade receivables $ 36.1 $ 19.9 Income tax receivable 7.4 10.6 Prepaid and other 15.7 12.4 Total other current assets $ 59.2 $ 42.9
Schedule of Other Current Liabilities	(In millions) September 30, December 31, Other Current Liabilities Customer volume rebates $ 28.6 $ 30.5 Accrued compensation (1) 23.0 28.0 Income tax payable 118.2 6.7 Accrued interest 8.5 20.8 Restructuring liabilities 15.2 1.1 Pension liabilities 1.0 0.4 Other accrued liabilities (2) 115.8 32.0 Total other current liabilities $ 310.3 $ 119.5 ________________________________ (1) Accrued compensation in the table above includes salaries and wages, as well as estimated current amounts due under the annual and long-term incentive programs. (2) Other accrued liabilities in the table above as of September 30, 2017 includes $55.1 million of deferred consideration related to the delayed closings associated with our divestiture of Darex, as discussed in Note 14.

Restructuring and Repositioni30

Restructuring and Repositioning Expenses (Tables)	9 Months Ended
	Sep. 30, 2017
Restructuring Cost and Reserve [Line Items]
Schedule of Restructuring Liability	The following table summarizes details of the Company’s restructuring liability activity: 2017 Plan (In millions) Severance and other employee costs Facility exit costs Other plans Total Balance, December 31, 2016 $ — $ — $ 1.1 $ 1.1 Expense 18.5 0.1 0.5 19.1 Payments (4.7 ) — (0.5 ) (5.2 ) Impact of foreign currency and other 0.2 — — 0.2 Balance, September 30, 2017 $ 14.0 $ 0.1 $ 1.1 $ 15.2
2017 Plan
Restructuring Cost and Reserve [Line Items]
Schedule of Restructuring and Repositioning Expenses	The following table summarizes restructuring expenses incurred related to the 2017 Plan and prior-period plans: Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Severance and other employee costs $ 2.1 $ 0.4 $ 19.0 $ 1.4 Facility exit costs and asset impairments 0.4 — 0.9 — Total restructuring expenses $ 2.5 $ 0.4 $ 19.9 $ 1.4 Less: restructuring expenses reflected in discontinued operations 0.4 — 6.9 — Total restructuring expenses from continuing operations $ 2.1 $ 0.4 $ 13.0 $ 1.4 GCP incurred restructuring costs related to its segments as follows: Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 SCC $ 0.7 $ 0.3 $ 6.2 $ 0.8 SBM (0.3 ) 0.1 4.1 0.6 Corporate 1.7 — 2.7 — Total restructuring expenses from continuing operations $ 2.1 $ 0.4 $ 13.0 $ 1.4 Restructuring expenses reflected in discontinued operations 0.4 — 6.9 — Total restructuring expenses $ 2.5 $ 0.4 $ 19.9 $ 1.4
Separation-Related Repositioning
Restructuring Cost and Reserve [Line Items]
Schedule of Restructuring and Repositioning Expenses	Separation-related repositioning expenses incurred for the periods presented were as follows: Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Professional fees $ — $ 3.1 $ 3.4 $ 7.3 Software and IT implementation fees — 0.8 0.9 2.5 Employee-related costs — 1.4 1.0 4.5 Total $ — $ 5.3 $ 5.3 $ 14.3

Other Comprehensive Income (L31

Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Schedule 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 GCP's other comprehensive income for the three and nine months ended September 30, 2017 and 2016 : Three Months Ended September 30, 2017 (In millions) Pre-Tax Amount Tax (Expense)/ Benefit After-Tax Amount Defined benefit pension and other postretirement plans: Other changes $ (0.3 ) $ — $ (0.3 ) Benefit plans, net (0.3 ) — (0.3 ) Currency translation adjustments 46.2 — 46.2 Gain from hedging activities 0.8 (0.3 ) 0.5 Other comprehensive income attributable to GCP shareholders $ 46.7 $ (0.3 ) $ 46.4 Nine Months Ended September 30, 2017 (In millions) Pre-Tax Amount Tax (Expense)/ Benefit After-Tax Amount Defined benefit pension and other postretirement plans: Other changes $ (0.3 ) $ — $ (0.3 ) Benefit plans, net (0.3 ) — (0.3 ) Currency translation adjustments 63.0 — 63.0 Loss from hedging activities (0.1 ) — (0.1 ) Other comprehensive income attributable to GCP shareholders $ 62.6 $ — $ 62.6 Three Months Ended September 30, 2016 (In millions) Pre-Tax Amount Tax (Expense)/ Benefit After-Tax Amount Defined benefit pension and other postretirement plans: Amortization of net actuarial gain $ 0.1 $ — $ 0.1 Other changes in funded status (0.1 ) — (0.1 ) Benefit plans, net — — — Currency translation adjustments 3.0 — 3.0 Loss from hedging activities (0.1 ) — (0.1 ) Other comprehensive income attributable to GCP shareholders $ 2.9 $ — $ 2.9 Nine Months Ended September 30, 2016 (In millions) Pre-Tax Amount Tax (Expense)/ Benefit After-Tax Amount Defined benefit pension and other postretirement plans: Amortization of net prior service credit $ (0.1 ) $ — $ (0.1 ) Amortization of net actuarial gain 0.1 — 0.1 Assumption of net prior service credit 1.2 (0.4 ) 0.8 Assumption of net actuarial loss (1.1 ) 0.4 (0.7 ) Other changes in funded status (0.9 ) 0.3 (0.6 ) Benefit plans, net (0.8 ) 0.3 (0.5 ) Currency translation adjustments 3.5 — 3.5 Loss from hedging activities (0.1 ) — (0.1 ) Other comprehensive income attributable to GCP shareholders $ 2.6 $ 0.3 $ 2.9
Schedule of Changes of Accumulated Other Comprehensive Income (Loss), Net of Tax	The following tables present the changes in accumulated other comprehensive income (loss), net of tax, for the nine months ended September 30, 2017 and 2016 : Nine Months Ended September 30, 2017 (In millions) Defined Benefit Pension and Other Postretirement Plans Currency Translation Adjustments (Losses) Gains from Hedging Activities Total Beginning balance $ 0.1 $ (147.7 ) $ — $ (147.6 ) Other comprehensive (loss) income before reclassifications (0.3 ) 63.0 (0.7 ) 62.0 Amounts reclassified from accumulated other comprehensive (loss) income — — 0.6 0.6 Net current-period other comprehensive (loss) income (0.3 ) 63.0 (0.1 ) 62.6 Ending balance $ (0.2 ) $ (84.7 ) $ (0.1 ) $ (85.0 ) Nine Months Ended September 30, 2016 (In millions) Defined Benefit Pension and Other Postretirement Plans Currency Translation Adjustments (Losses) Gains from Hedging Activities Total Beginning balance $ 0.1 $ (127.8 ) $ — $ (127.7 ) Other comprehensive income (loss) before reclassifications — 3.5 (1.2 ) 2.3 Amounts reclassified from accumulated other comprehensive income (loss) (0.5 ) — 1.1 0.6 Net current-period other comprehensive (loss) income (0.5 ) 3.5 (0.1 ) 2.9 Ending balance $ (0.4 ) $ (124.3 ) $ (0.1 ) $ (124.8 )

Stock Incentive Plans (Tables)

Stock Incentive Plans (Tables)	9 Months Ended
	Sep. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Assumptions for Estimating the Fair Value of Stock Options	The following summarizes GCP's assumptions for estimating the fair value of stock options granted during 2017 : Assumptions used to calculate expense for stock option Nine Months Ended September 30, 2017 Risk-free interest rate 1.83 - 2.10% Average life of options (years) 5.5 - 6.5 Volatility 31.42 - 31.96% Dividend yield — Average fair value per stock option $9.16
Summary of Stock Option Activity	The following table summarizes GCP stock option activity for the nine months ended September 30, 2017 : Stock Option Activity Number Of Weighted Weighted Aggregated Outstanding, December 31, 2016 2,122 $ 16.92 3.57 $ 20,748 Options exercised 493 13.91 Options forfeited/expired/canceled 120 19.64 Options granted 240 26.48 Outstanding, September 30, 2017 1,749 18.90 3.55 20,691 Exercisable September 30, 2017 944 $ 17.81 2.35 $ 12,190
Summary of Restricted Stock Units Award Activity	GCP’s RSU activity for the nine months ended September 30, 2017 is as follows: RSU Activity Number Of Weighted Outstanding, December 31, 2016 538 $ 17.22 RSUs settled 113 17.23 RSUs forfeited 84 18.26 RSUs granted 95 26.42 RSUs outstanding, September 30, 2017 436 $ 19.02
Schedule of Restricted Stock Units Vesting and Settlements	GCP's expectations of future RSU vesting and settlement are as follows: Year Number of Shares Vesting (in thousands) Settled in Cash Settled in Stock 2017 20 —% 100% 2018 179 11% 89% 2019 212 —% 100% 2020 25 —% 100%

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
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 (loss) earnings per share: Three Months Ended September 30, Nine Months Ended September 30, (In millions, except per share amounts) 2017 2016 2017 2016 Numerators Net (loss) income from continuing operations attributable to GCP shareholders $ (18.1 ) $ 10.9 $ (41.8 ) $ 33.2 Income from discontinued operations, net of income taxes $ 677.3 $ 10.4 $ 679.4 $ 36.2 Net income attributable to GCP shareholders $ 659.2 $ 21.3 $ 637.6 $ 69.4 Denominators Weighted average common shares—basic calculation 71.6 71.0 71.2 70.8 Dilutive effect of employee stock awards (1) — 1.2 — 0.8 Weighted average common shares—diluted calculation 71.6 72.2 71.2 71.6 Basic (loss) earnings per share Net (loss) income from continuing operations attributable to GCP shareholders $ (0.25 ) $ 0.15 $ (0.59 ) $ 0.47 Income from discontinued operations, net of income taxes $ 9.46 $ 0.15 $ 9.54 $ 0.51 Net income attributable to GCP shareholders (2) $ 9.21 $ 0.30 $ 8.96 $ 0.98 Diluted (loss) earnings per share Net (loss) income from continuing operations attributable to GCP shareholders $ (0.25 ) $ 0.15 $ (0.59 ) $ 0.46 Income from discontinued operations, net of income taxes $ 9.46 $ 0.14 $ 9.54 $ 0.51 Net income attributable to GCP shareholders (2) $ 9.21 $ 0.30 $ 8.96 $ 0.97 ______________________________ (1) Dilutive effect only applicable to periods where there is net income from continuing operations. (2) Amounts may not sum due to rounding.

Related Party Transactions an34

Related Party Transactions and Transactions with Grace (Tables)	9 Months Ended
	Sep. 30, 2017
Related Party Transactions [Abstract]
Components of Net Transfers to Parent	The components of the net transfers to parent as of September 30, 2016 are as follows: (In millions) 2016 Cash pooling and general financing activities $ (685.1 ) GCP expenses funded by parent 6.6 Corporate costs allocations 2.0 Provision for income taxes 4.3 Total net transfers to parent (672.2 ) Other, net (86.5 ) Transfers to parent, net, per Consolidated Statement of Cash Flows $ (758.7 )

Operating Segment Information (

Operating Segment Information (Tables)	9 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Schedule of Operating Segment Data	Operating Segment Data Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Net Sales Specialty Construction Chemicals $ 156.2 $ 162.8 $ 449.1 $ 466.6 Specialty Building Materials 126.2 100.6 345.8 318.5 Total net sales $ 282.4 $ 263.4 $ 794.9 $ 785.1 Segment Operating Income Specialty Construction Chemicals $ 15.7 $ 23.2 $ 44.5 $ 53.7 Specialty Building Materials 30.1 25.6 80.6 88.9 Total segment operating income $ 45.8 $ 48.8 $ 125.1 $ 142.6
Reconciliation of Operating Segment Data to Financial Statements	Total segment operating income for the three and nine months ended September 30, 2017 and 2016 , is reconciled below to "(Loss) income from continuing operations before income taxes" presented in the accompanying Consolidated Statements of Operations: Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Total segment operating income $ 45.8 $ 48.8 $ 125.1 $ 142.6 Corporate costs (1) (7.5 ) (9.0 ) (28.9 ) (29.1 ) Certain pension costs (2.1 ) (1.8 ) (7.0 ) (5.4 ) Loss on sale of product line — — (2.1 ) — Currency and other financial losses in Venezuela (36.7 ) — (39.1 ) — Litigation settlement (4.0 ) — (4.0 ) — Repositioning expenses (1.1 ) (5.3 ) (6.8 ) (14.3 ) Restructuring expenses and asset impairments (2.1 ) (0.4 ) (13.0 ) (1.4 ) Pension MTM adjustment and other related costs, net (3.0 ) — (2.9 ) (2.7 ) Gain on termination and curtailment of pension and other postretirement plans 0.8 0.2 5.9 2.6 Third-party and other acquisition-related costs (2.0 ) (0.3 ) (5.0 ) (0.3 ) Amortization of acquired inventory fair value adjustment (0.2 ) — (2.9 ) — Tax indemnification adjustments — — (2.4 ) — Net income attributable to noncontrolling interests 0.1 0.2 0.2 0.9 Other financing costs (6.0 ) (1.2 ) (6.0 ) (1.2 ) Interest expense, net (14.5 ) (17.6 ) (49.0 ) (47.8 ) (Loss) income from continuing operations before income taxes $ (32.5 ) $ 13.6 $ (37.9 ) $ 43.9 _______________________________ (1) Corporate costs include $5.4 million and $7.0 million of allocated costs in the nine months ended September 30, 2017 and 2016 , respectively, and $2.6 million of allocated costs in the three months ended September 30, 2016 that were previously reported within the Darex operating segment. Such costs did not qualify to be reclassified to discontinued operations.
Schedule of Geographic Area Data	The table below presents information related to the geographic areas in which GCP operates. Sales are attributed to geographic areas based on customer location. Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Net Sales United States $ 132.5 $ 119.6 $ 374.2 $ 353.1 Canada and Puerto Rico 9.0 9.0 21.8 24.9 Total North America 141.5 128.6 396.0 378.0 Europe Middle East Africa 67.0 55.3 178.9 173.9 Asia Pacific 58.0 61.3 168.4 180.9 Latin America 15.9 18.2 51.6 52.3 Total $ 282.4 $ 263.4 $ 794.9 $ 785.1

Discontinued Operations (Tables

Discontinued Operations (Tables)	9 Months Ended
	Sep. 30, 2017
Discontinued Operations and Disposal Groups [Abstract]
Reconciliation of Gain on Disposal	Refer to the table below for a reconciliation of the gain recorded on the sale of Darex at the closing date. (In millions) Net proceeds included in gain recognized in third quarter of 2017 $ 1,000.2 Less: Transaction costs 15.9 Less: Net assets derecognized in third quarter of 2017 100.6 Gain recognized in third quarter of 2017 before income taxes 883.7 Less: Tax effect of gain recognized in third quarter of 2017 200.0 Gain recognized in third quarter of 2017 after income taxes $ 683.7
Financial Results and Other Effects Related to Discontinued Operations	"Income from discontinued operations, net of income taxes" in the accompanying Statements of Operations is comprised of the following: Three Months Ended September 30, Nine Months Ended September 30, (In millions) 2017 2016 2017 2016 Net sales $ 9.1 $ 79.1 $ 156.9 $ 237.8 Cost of goods sold 6.0 51.7 104.6 152.2 Selling, general and administrative expenses 6.6 8.0 40.1 24.1 Research and development expenses 0.1 1.2 2.3 3.5 Restructuring expenses 0.4 — 6.9 — Gain on sale of business (883.7 ) — (883.7 ) — Other non-operating expenses, net 2.4 0.7 7.5 1.8 Provision for income taxes (200.0 ) (7.1 ) (199.7 ) (20.0 ) Less: Net income attributable to noncontrolling interests — — (0.1 ) — Income from discontinued operations, net of income taxes $ 677.3 $ 10.4 $ 679.4 $ 36.2 The carrying amounts of the major classes of assets and liabilities of Darex classified as "held for sale" as of September 30, 2017 and December 31, 2016 consist of the following: (In millions) September 30, 2017 December 31, 2016 Cash and cash equivalents $ — $ 16.3 Trade accounts receivable 7.9 50.5 Inventories 7.9 32.3 Other current assets 1.0 8.9 Current assets held for sale 16.8 108.0 Properties and equipment, net 1.9 39.6 Goodwill — 4.4 Technology and other intangible assets, net — 0.4 Deferred income taxes — 6.4 Other assets 0.6 4.6 Noncurrent assets held for sale 2.5 55.4 Accounts payable 6.8 26.7 Other current liabilities 1.3 21.5 Current liabilities held for sale 8.1 48.2 Deferred income taxes — 2.3 Underfunded and unfunded defined benefit pension plans 0.3 14.8 Other liabilities — 3.8 Noncurrent liabilities held for sale $ 0.3 $ 20.9

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2017
Business Combinations [Abstract]
Schedule of Aggregate Purchase Price Allocation	The following table presents the aggregate purchase price allocation as of September 30, 2017. (In millions) Net Assets Acquired Accounts receivable, net $ 6.8 Other current assets 3.1 Inventories 4.2 Properties and equipment, net 3.4 Goodwill 59.6 Intangible assets 26.9 Accounts payable (2.9 ) Other current liabilities (4.2 ) Other liabilities (5.8 ) Net assets acquired $ 91.1
Schedule of Intangible Assets Acquired	The table below presents the intangible assets acquired as part of the acquisition of Stirling Lloyd and the periods over which they will be amortized. Amount (In millions) Weighted-Average Amortization Period (in years) Customer Lists $ 15.0 10 Technology 9.8 11 Trademarks 2.1 10 Total $ 26.9

Basis of Presentation and Sum38

Basis of Presentation and Summary of Significant Accounting and Financial Reporting Policies - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)segment	Sep. 30, 2016USD ($)	Jul. 03, 2017USD ($)
Class of Stock [Line Items]
Number of operating segments | segment			2
Loss in Venezuela, before taxes	$ (36.7)	$ 0	$ (38.3)	$ 0
Loss in Venezuela, net of taxes	(23.8)
Foreign Exchange Reameasurement Loss	3.4
Loss in Venezuela
Class of Stock [Line Items]
Cumulative translation adjustment	33.4
Foreign Exchange Reameasurement Loss	2.9
Other income
Class of Stock [Line Items]
Foreign Exchange Reameasurement Loss	0.5
Darex | Disposed of by sale
Class of Stock [Line Items]
Consideration to be received					$ 1,060
Pre-tax gain on sale of disposal group	$ 883.7

Inventories - Schedule of Inven

Inventories - Schedule of Inventory (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Raw materials	$ 40.2	$ 35.7
In process	4	3.6
Finished products and other	64.2	50
Total inventories	$ 108.4	$ 89.3

Inventories - Narrative (Detail

Inventories - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Inventory [Line Items]
Finished products purchased	$ 64.2	$ 50
Finished Products Purchased
Inventory [Line Items]
Finished products purchased	$ 12.2	$ 10.9

Debt and Other Financial Inst41

Debt and Other Financial Instruments - Components of Debt (Details) - USD ($) $ in Millions	Jul. 31, 2017	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Debt Instrument [Line Items]
Total debt		$ 544.1		$ 830.9
Debt payable within one year		23.8		47.9
Debt payable after one year		$ 520.3		$ 783
Weighted average interest rates on total debt		9.40%		7.50%
Repayments of secured debt		$ 416.6	$ 30.7
Senior Notes
Debt Instrument [Line Items]
Total debt		518.4		$ 517.7
Term Loan
Debt Instrument [Line Items]
Total debt		0		266.2
Write off of unamortized debt discount	$ 2.1
Write off of deferred debt issuance cost	3.9
Line of credit
Debt Instrument [Line Items]
Total debt		25.7		22
Line of credit | Revolving Credit
Debt Instrument [Line Items]
Total debt		$ 0		$ 25
Credit Agreement | Term Loan | Secured Debt
Debt Instrument [Line Items]
Repayments of secured debt	$ 272.6

Debt and Other Financial Inst42

Debt and Other Financial Instruments - Components of Debt (Additional Information) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016	Jan. 27, 2016
Senior Notes
Debt Instrument [Line Items]
Stated interest rate	9.50%		9.50%
Unamortized debt issuance cost	$ 6.6	$ 7.3
Term Loan
Debt Instrument [Line Items]
Unamortized debt issuance cost		4.3
Unamortized discount		$ 2.4
Revolving Credit | LIBOR | Other Borrowings
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%

Debt and Other Financial Inst43

Debt and Other Financial Instruments - Principal Maturities of Debt Outstanding (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
2,017	$ 23.4
2,018	0.9
2,019	0.9
2,020	0.5
2,021	0
Thereafter	518.4
Total debt	$ 544.1	$ 830.9

Debt and Other Financial Inst44

Debt and Other Financial Instruments - Narrative (Details) - USD ($)	Jul. 31, 2017	Jul. 03, 2017	Mar. 31, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Feb. 03, 2016	Jan. 27, 2016
Debt Instrument [Line Items]
Repayments of secured debt				$ 416,600,000	$ 30,700,000
Distribution to Grace related to the Separation			$ 750,000,000	750,000,000
Debt proceeds retained to meet operating requirements and to pay fees associated with the Separation			$ 50,000,000
Long-term debt				544,100,000		$ 830,900,000
Darex | Disposed of by sale
Debt Instrument [Line Items]
Consideration to be received		$ 1,060,000,000
Required period for prepayment of debt or investment in Company using net proceeds from sale		18 months
Term Loan
Debt Instrument [Line Items]
Write off of unamortized debt discount	$ 2,100,000
Write off of deferred debt issuance cost	3,900,000
Long-term debt				$ 0		266,200,000
Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount								$ 525,000,000
Stated interest rate				9.50%				9.50%
Debt issuance costs, gross						8,000,000
Long-term debt				$ 518,400,000		517,700,000
Related Party Debt
Debt Instrument [Line Items]
Long-term debt							$ 42,000,000
Secured Debt | Term Loan
Debt Instrument [Line Items]
Debt issuance costs, gross						5,000,000
Secured Debt | Revolving Credit
Debt Instrument [Line Items]
Outstanding letters of credit				10,000,000
Line of credit debt issuance costs, gross						5,200,000
Line of credit, unamortized debt issuance costs				3,500,000		$ 4,200,000
Credit Agreement | United States
Debt Instrument [Line Items]
Pledged equity to credit facilities, percentage							100.00%
Credit Agreement | United Kingdom
Debt Instrument [Line Items]
Pledged equity to credit facilities, percentage							65.00%
Credit Agreement | Secured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity							$ 525,000,000
Credit Agreement | Secured Debt | Term Loan
Debt Instrument [Line Items]
Aggregate principal amount							275,000,000
Repayments of secured debt	$ 272,600,000
Credit Agreement | Secured Debt | Term Loan | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate						3.50%
Credit Agreement | Secured Debt | Term Loan | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate						4.50%
Credit Agreement | Secured Debt | Revolving Credit
Debt Instrument [Line Items]
Maximum borrowing capacity							$ 250,000,000
Amended Credit Agreement | Secured Debt | Term Loan | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate						2.25%
Amended Credit Agreement | Secured Debt | Term Loan | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate						3.25%
Amended Credit Agreement | Secured Debt | Revolving Credit
Debt Instrument [Line Items]
Outstanding draw on revolving loans				0
Available credit under revolving loans				$ 240,000,000
Amended Credit Agreement | Secured Debt | Revolving Credit | Base Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate				0.50%
Amended Credit Agreement | Secured Debt | Revolving Credit | Base Rate | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate				1.00%
Amended Credit Agreement | Secured Debt | Revolving Credit | LIBOR | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate				1.50%
Amended Credit Agreement | Secured Debt | Revolving Credit | LIBOR | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate				2.00%

Debt and Other Financial Inst45

Debt and Other Financial Instruments - Carrying Amounts and Fair Values of Debt Instruments (Details) - USD ($) $ in Millions	Jul. 31, 2017	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Jan. 27, 2016
Debt Instrument [Line Items]
Repayments of secured debt		$ 416.6	$ 30.7
Senior Notes
Debt Instrument [Line Items]
Stated interest rate		9.50%			9.50%
Term Loan
Debt Instrument [Line Items]
Write off of unamortized debt discount	$ 2.1
Write off of deferred debt issuance cost	3.9
Term Loan | Secured Debt | Credit Agreement
Debt Instrument [Line Items]
Repayments of secured debt	$ 272.6
Carrying Amount
Debt Instrument [Line Items]
Fair value		$ 544.1		$ 830.9
Carrying Amount | Senior Notes
Debt Instrument [Line Items]
Fair value		518.4		517.7
Carrying Amount | Term Loan
Debt Instrument [Line Items]
Fair value		0		266.2
Carrying Amount | Other Borrowings
Debt Instrument [Line Items]
Fair value		25.7		22
Carrying Amount | Other Borrowings | Revolving Credit
Debt Instrument [Line Items]
Fair value		0		25
Fair Value | Level 2 Inputs
Debt Instrument [Line Items]
Fair value		618.3		924.7
Fair Value | Senior Notes | Level 2 Inputs
Debt Instrument [Line Items]
Fair value		592.6		603.1
Fair Value | Term Loan | Level 2 Inputs
Debt Instrument [Line Items]
Fair value		0		274.6
Fair Value | Other Borrowings | Level 2 Inputs
Debt Instrument [Line Items]
Fair value		25.7		22
Fair Value | Other Borrowings | Revolving Credit | Level 2 Inputs
Debt Instrument [Line Items]
Fair value		$ 0		$ 25

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Sep. 30, 2017	Sep. 30, 2016
Operating Loss Carryforwards [Line Items]
Provision for income taxes	$ (14.5)	$ 2.5		$ 3.7	$ 9.8
Effective tax rate	44.60%	18.40%		9.80%	22.30%
Federal income tax rate				35.00%
Tax on undistributed foreign earnings	$ (2.9)	$ 0	$ 6.5	$ 3.6	$ 0
Foreign operating loss carryforwards				13.9
MEXICO
Operating Loss Carryforwards [Line Items]
Tax on undistributed foreign earnings	(7.5)
United Kingdom
Operating Loss Carryforwards [Line Items]
Tax on undistributed foreign earnings	4.6
Darex | Discontinued Operations
Operating Loss Carryforwards [Line Items]
Provision (benefit) for income taxes	$ 200	$ 7.1		$ 199.7	$ 20

Income Taxes - Tax Reconciliati

Income Taxes - Tax Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Sep. 30, 2017	Sep. 30, 2016
Income Tax Disclosure [Abstract]
Income tax (benefit) expense at U.S. federal income tax rate	$ (11.4)	$ 4.8		$ (13.3)	$ 15.4
Change in income tax (benefit) expense resulting from:
Valuation allowance	0	0		13.9	0
Tax on undistributed foreign earnings	(2.9)	0	$ 6.5	3.6	0
Effect of tax rates in foreign jurisdictions	(0.1)	(0.5)		0.1	(3.9)
Permanent items and other	(0.1)	(1.8)		(0.6)	(1.7)
Income tax (benefit) expense	$ (14.5)	$ 2.5		$ 3.7	$ 9.8

Pension Plans and Other Postr48

Pension Plans and Other Postretirement Benefit Plans - Narrative (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Sep. 30, 2016	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Pension plans and other postretirement benefit plans
Overfunded defined benefit pension plans	$ 22.1				$ 22.1		$ 21.2
Underfunded and unfunded defined benefit pension plans	85.6				85.6		83.2
Curtailment gain					$ 5.8	$ 2.6
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	1.1		$ 1		$ 3.6	3
Non-U.S.
Pension plans and other postretirement benefit plans
Contributions by employer					1.9	1.7
Postretirement Life Insurance
Pension plans and other postretirement benefit plans
Curtailment gain on elimination of retiree life insurance benefits				$ 1
Pension
Pension plans and other postretirement benefit plans
Combined balance of underfunded and unfunded plans included as liabilities	86.6				86.6
Pension liabilities included in other current liabilities	1				1		0.4
Underfunded and unfunded defined benefit pension plans	85.6				85.6		83.2
Curtailment gain		$ 5.1
Pension | Non-U.S.
Pension plans and other postretirement benefit plans
Curtailment gain on elimination of retiree life insurance benefits	14.3		0.2		14.3	1.6
Mark-to-market remeasurement gain	(1.7)	(0.1)	0		(1.6)	0
Pension | Non-U.S. | Discontinued Operations
Pension plans and other postretirement benefit plans
Mark-to-market remeasurement gain	(0.1)
Service cost, interest cost, and expected return on plan assets			0.3		0.5	0.9
Pension | U.S.
Pension plans and other postretirement benefit plans
Curtailment gain on elimination of retiree life insurance benefits	2.8		0		8.4	0
Mark-to-market remeasurement gain	(1.2)		$ 0		(1.2)	$ 0
Pension | Other income (expense)
Pension plans and other postretirement benefit plans
Curtailment gain	0.7	$ 0.5
Pension | Income (loss) from discontinued operations | Non-U.S. | Darex | Disposed of by sale
Pension plans and other postretirement benefit plans
Curtailment gain	14.3				0
Pension | Income (loss) from discontinued operations | U.S. | Darex | Disposed of by sale
Pension plans and other postretirement benefit plans
Curtailment gain	2.1				0
Pension | Other income | Non-U.S. | Darex | Disposed of by sale
Pension plans and other postretirement benefit plans
Mark-to-market remeasurement gain	1.8				1.8
Pension | Other income | U.S. | Darex | Disposed of by sale
Pension plans and other postretirement benefit plans
Mark-to-market remeasurement gain	1.2				1.2
Pension | Overfunded defined benefit pension plans
Pension plans and other postretirement benefit plans
Overfunded defined benefit pension plans	$ 22.1				$ 22.1		$ 21.2

Pension Plans and Other Postr49

Pension Plans and Other Postretirement Benefit Plans - Net Funded Status of Over-Funded, Underfunded, and Unfunded Pension Plans (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Pension plans and other postretirement benefit plans
Overfunded defined benefit pension plans	$ 22.1	$ 21.2
Underfunded defined benefit pension plans	(85.6)	(83.2)
Pension
Pension plans and other postretirement benefit plans
Underfunded defined benefit pension plans	(85.6)	(83.2)
Pension liabilities included in other current liabilities	(1)	(0.4)
Net funded status	(64.5)	(62.4)
Overfunded defined benefit pension plans | Pension
Pension plans and other postretirement benefit plans
Overfunded defined benefit pension plans	22.1	21.2
Underfunded defined benefit pension plans | Pension
Pension plans and other postretirement benefit plans
Underfunded defined benefit pension plans	(57.9)	(55.6)
Unfunded defined benefit pension plans | Pension
Pension plans and other postretirement benefit plans
Underfunded defined benefit pension plans	$ (27.7)	$ (27.6)

Pension Plans and Other Postr50

Pension Plans and Other Postretirement Benefit Plans - Components of Net Periodic Benefit Cost (Income) (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Other Post Retirement
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
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) cost				0	(0.1)
Amortization of net deferred actuarial loss	0		0.1	0	0.1
Mark-to-market adjustment	0		0	0	0
Gain on curtailments, settlements and terminations	0		0	0	(1)
Net periodic benefit (income) cost	0		0.1	0	(1)
Less: Discontinued operations (income) cost	0		0	0	0
Net periodic benefit cost (income) from continuing operations	0		0.1	0	(1)
U.S. | Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	1.6		1.6	5.3	4.6
Interest cost	1.3		1.1	4.2	3.5
Expected return on plan assets	(1.4)		(1.2)	(4.2)	(3.7)
Amortization of prior service (credit) cost				0	0
Amortization of net deferred actuarial loss	0		0	0	0
Mark-to-market adjustment	1.2		0	1.2	0
Gain on curtailments, settlements and terminations	(2.8)		0	(8.4)	0
Net periodic benefit (income) cost	(0.1)		1.5	(1.9)	4.4
Less: Discontinued operations (income) cost	(2.1)		0	(2.6)	0
Net periodic benefit cost (income) from continuing operations	2		1.5	0.7	4.4
Non-U.S. | Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	0.8		0.8	3	2.5
Interest cost	1.4		1.9	4.3	6
Expected return on plan assets	(1.6)		(2.1)	(5.1)	(6.6)
Amortization of prior service (credit) cost				0	0
Amortization of net deferred actuarial loss	0		0	0	0
Mark-to-market adjustment	1.7	$ 0.1	0	1.6	0
Gain on curtailments, settlements and terminations	(14.3)		(0.2)	(14.3)	(1.6)
Net periodic benefit (income) cost	(12)		0.4	(10.5)	0.3
Less: Discontinued operations (income) cost	(14.4)		0.3	(13.9)	0.9
Net periodic benefit cost (income) from continuing operations	$ 2.4		$ 0.1	$ 3.4	$ (0.6)

Other Balance Sheet Accounts -

Other Balance Sheet Accounts - Other Current Assets (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Other Current Assets:
Non-trade receivables	$ 36.1	$ 19.9
Income tax receivable	7.4	10.6
Prepaid and other	15.7	12.4
Total other current assets	$ 59.2	$ 42.9

Other Balance Sheet Accounts 52

Other Balance Sheet Accounts - Other Current Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Other Current Liabilities
Customer volume rebates	$ 28.6	$ 30.5
Accrued compensation	23	28
Income tax payable	118.2	6.7
Accrued interest	8.5	20.8
Restructuring liabilities	15.2	1.1
Pension liabilities	1	0.4
Other accrued liabilities	115.8	32
Total other current liabilities	310.3	$ 119.5
Disposed of by sale | Darex
Other Current Liabilities
Other accrued liabilities	$ 55.1

Commitments and Contingent Li53

Commitments and Contingent Liabilities (Details)	Nov. 12, 2015defendantindividual	Sep. 30, 2017USD ($)
Loss Contingencies [Line Items]
Environmental liabilities | $		$ 0
Library Gardens Balcony Litigation, Lead Case Beary v. Blackrock, Inc. | Damages from Product Defects
Loss Contingencies [Line Items]
Number of lawsuits filed on behalf of individuals who died | individual	6
Number of injured defendants | defendant	7
Number of additional defendants | defendant	20
Number of construction company defendants | defendant	2
Amended Credit Agreement | Standby Letter of Credit
Loss Contingencies [Line Items]
Gross financial assurances issued and outstanding | $		10,000,000
Selling, General and Administrative Expenses | Library Gardens Balcony Litigation, Lead Case Beary v. Blackrock, Inc. | Damages from Product Defects
Loss Contingencies [Line Items]
Litigation settlement expense | $		$ 4,000,000

Restructuring and Repositioni54

Restructuring and Repositioning Expenses - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		17 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017
Restructuring Cost and Reserve [Line Items]
Expense	$ 1.1	$ 5.3	$ 6.8	$ 14.3
2017 Plan | Minimum
Restructuring Cost and Reserve [Line Items]
Estimated transition expenses	28		28		$ 22
2017 Plan | Maximum
Restructuring Cost and Reserve [Line Items]
Estimated transition expenses	32		32		26
2017 Plan, Restructuring Activities
Restructuring Cost and Reserve [Line Items]
Estimated transition expenses	25		25
Estimated transition expenses to be classified within discontinued operations	9		9
2017 Plan, Repositioning Activities
Restructuring Cost and Reserve [Line Items]
Estimated transition expenses	6		6
Expense	1.1		1.5
Total cash payments for repositioning costs			1.2
2017 Plan, Repositioning Activities | Capital expenditures
Restructuring Cost and Reserve [Line Items]
Estimated transition expenses	9		9
Increase in expected cost	3
Separation-Related Repositioning
Restructuring Cost and Reserve [Line Items]
Expense	$ 0	$ 5.3	5.3	14.3	$ 20.5
Separation-Related Repositioning | Capital expenditures
Restructuring Cost and Reserve [Line Items]
Total cash payments for repositioning costs			1.9	5.7
Separation-Related Repositioning | Professional fees and employee-related costs
Restructuring Cost and Reserve [Line Items]
Total cash payments for repositioning costs			$ 4.2	14.7
Separation-Related Repositioning | Repositioning tax expense
Restructuring Cost and Reserve [Line Items]
Total cash payments for repositioning costs				$ 6.9

Restructuring and Repositioni55

Restructuring and Repositioning Expenses - Restructuring Expenses (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Restructuring Cost and Reserve [Line Items]
Total restructuring expenses	$ 2.5	$ 0.4	$ 19.9	$ 1.4
Less: restructuring expenses reflected in discontinued operations	0.4	0	6.9	0
Total restructuring expenses from continuing operations	2.1	0.4	13	1.4
Severance and other employee costs
Restructuring Cost and Reserve [Line Items]
Total restructuring expenses	2.1	0.4	19	1.4
Facility exit costs and asset impairments
Restructuring Cost and Reserve [Line Items]
Total restructuring expenses	$ 0.4	$ 0	$ 0.9	$ 0

Restructuring and Repositioni56

Restructuring and Repositioning Expenses - Restructuring Costs by Segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Restructuring Cost and Reserve [Line Items]
Total restructuring expenses from continuing operations	$ 2.1	$ 0.4	$ 13	$ 1.4
Restructuring expenses reflected in discontinued operations	0.4	0	6.9	0
Total restructuring expenses	2.5	0.4	19.9	1.4
Operating Segments | SCC
Restructuring Cost and Reserve [Line Items]
Total restructuring expenses from continuing operations	0.7	0.3	6.2	0.8
Operating Segments | SBM
Restructuring Cost and Reserve [Line Items]
Total restructuring expenses from continuing operations	(0.3)	0.1	4.1	0.6
Corporate
Restructuring Cost and Reserve [Line Items]
Total restructuring expenses from continuing operations	$ 1.7	$ 0	$ 2.7	$ 0

Restructuring and Repositioni57

Restructuring and Repositioning Expenses - Restructuring Liability (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Restructuring Reserve [Roll Forward]
Expense	$ 1.1	$ 5.3	$ 6.8	$ 14.3
Other plans
Restructuring Reserve [Roll Forward]
Balance, December 31, 2016			1.1
Expense			0.5
Payments			(0.5)
Impact of foreign currency and other			0
Balance, September 30, 2017	1.1		1.1
Total
Restructuring Reserve [Roll Forward]
Balance, December 31, 2016			1.1
Expense			19.1
Payments			(5.2)
Impact of foreign currency and other			0.2
Balance, September 30, 2017	15.2		15.2
Severance and other employee costs | 2017 Plan
Restructuring Reserve [Roll Forward]
Balance, December 31, 2016			0
Expense			18.5
Payments			(4.7)
Impact of foreign currency and other			0.2
Balance, September 30, 2017	14		14
Facility exit costs | 2017 Plan
Restructuring Reserve [Roll Forward]
Balance, December 31, 2016			0
Expense			0.1
Payments			0
Impact of foreign currency and other			0
Balance, September 30, 2017	$ 0.1		$ 0.1

Restructuring and Repositioni58

Restructuring and Repositioning Expenses - Separation-Related Repositioning Expenses (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		17 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017
Restructuring Cost and Reserve [Line Items]
Expense	$ 1.1	$ 5.3	$ 6.8	$ 14.3
Separation-Related Repositioning
Restructuring Cost and Reserve [Line Items]
Expense	0	5.3	5.3	14.3	$ 20.5
Separation-Related Repositioning | Professional fees
Restructuring Cost and Reserve [Line Items]
Expense	0	3.1	3.4	7.3
Separation-Related Repositioning | Software and IT implementation fees
Restructuring Cost and Reserve [Line Items]
Expense	0	0.8	0.9	2.5
Separation-Related Repositioning | Employee-related costs
Restructuring Cost and Reserve [Line Items]
Expense	$ 0	$ 1.4	$ 1	$ 4.5

Other Comprehensive Income (L59

Other Comprehensive Income (Loss) - Pre-Tax, Tax, and After-Tax Components of Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
After-Tax Amount
Total other comprehensive income	$ 46.4	$ 2.9	$ 62.6	$ 3.1
Other comprehensive income attributable to GCP shareholders
Pre-Tax Amount
Other comprehensive income (loss), pre-tax amount	46.7	2.9	62.6	2.6
Tax Benefit/ (Expense)
Other comprehensive income (loss), tax	(0.3)	0	0	0.3
After-Tax Amount
Defined benefit pension and other postretirement plans, after-tax			62	2.3
Total other comprehensive income	46.4	2.9	62.6	2.9
Amortization of net prior service cost included in net periodic benefit cost, after-tax			(0.6)	(0.6)
Amortization of net prior service credit
Pre-Tax Amount
Amortization of net prior service cost included in net periodic benefit cost, pre-tax amount				(0.1)
Tax Benefit/ (Expense)
Amortization of net prior service cost included in net periodic benefit cost, tax				0
After-Tax Amount
Amortization of net prior service cost included in net periodic benefit cost, after-tax				(0.1)
Amortization of net actuarial gain
Pre-Tax Amount
Defined benefit pension and other postretirement plans, pre-tax amount		0.1		0.1
Tax Benefit/ (Expense)
Defined benefit pension and other postretirement plans, tax		0		0
After-Tax Amount
Defined benefit pension and other postretirement plans, after-tax		0.1		0.1
Assumption of net prior service credit
Pre-Tax Amount
Defined benefit pension and other postretirement plans, pre-tax amount				1.2
Tax Benefit/ (Expense)
Defined benefit pension and other postretirement plans, tax				(0.4)
After-Tax Amount
Defined benefit pension and other postretirement plans, after-tax				0.8
Assumption of net actuarial loss
Pre-Tax Amount
Defined benefit pension and other postretirement plans, pre-tax amount				(1.1)
Tax Benefit/ (Expense)
Defined benefit pension and other postretirement plans, tax				0.4
After-Tax Amount
Defined benefit pension and other postretirement plans, after-tax				(0.7)
Other changes in funded status
Pre-Tax Amount
Defined benefit pension and other postretirement plans, pre-tax amount	(0.3)	(0.1)	(0.3)	(0.9)
Tax Benefit/ (Expense)
Defined benefit pension and other postretirement plans, tax	0	0		0.3
After-Tax Amount
Defined benefit pension and other postretirement plans, after-tax	(0.3)	(0.1)	(0.3)	(0.6)
Benefit plans, net
Pre-Tax Amount
Other comprehensive income (loss), pre-tax amount	(0.3)	0	(0.3)	(0.8)
Tax Benefit/ (Expense)
Other comprehensive income (loss), tax	0	0		0.3
After-Tax Amount
Defined benefit pension and other postretirement plans, after-tax			(0.3)	0
Total other comprehensive income	(0.3)	0	(0.3)	(0.5)
Amortization of net prior service cost included in net periodic benefit cost, after-tax			0	0.5
Currency translation adjustments
Pre-Tax Amount
Other comprehensive income (loss), pre-tax amount	46.2	3	63	3.5
Tax Benefit/ (Expense)
Other comprehensive income (loss), tax	0	0	0	0
After-Tax Amount
Defined benefit pension and other postretirement plans, after-tax			63	3.5
Total other comprehensive income	46.2	3	63	3.5
Amortization of net prior service cost included in net periodic benefit cost, after-tax			0	0
Gain (loss) from hedging activities
Pre-Tax Amount
Other comprehensive income (loss), pre-tax amount	0.8	(0.1)	(0.1)	(0.1)
Tax Benefit/ (Expense)
Other comprehensive income (loss), tax	(0.3)	0	0	0
After-Tax Amount
Defined benefit pension and other postretirement plans, after-tax			(0.7)	(1.2)
Total other comprehensive income	$ 0.5	$ (0.1)	(0.1)	(0.1)
Amortization of net prior service cost included in net periodic benefit cost, after-tax			$ (0.6)	$ (1.1)

Other Comprehensive Income (L60

Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss), Net of Tax (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017USD ($)country	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)country	Sep. 30, 2016USD ($)
Changes in accumulated other comprehensive income (loss), net of tax
Beginning balance			$ (139)	$ 474.1
Total other comprehensive income	$ 46.4	$ 2.9	62.6	3.1
Ending balance	$ 572.2	(118.4)	$ 572.2	(118.4)
Number of countries in which entity operates, more than | country	35		35
Defined Benefit Pension and Other Postretirement Plans
Changes in accumulated other comprehensive income (loss), net of tax
Beginning balance			$ 0.1	0.1
Other comprehensive (loss) income before reclassifications			(0.3)	0
Amounts reclassified from accumulated other comprehensive (loss) income			0	(0.5)
Total other comprehensive income	$ (0.3)	0	(0.3)	(0.5)
Ending balance	(0.2)	(0.4)	(0.2)	(0.4)
Currency Translation Adjustments
Changes in accumulated other comprehensive income (loss), net of tax
Beginning balance			(147.7)	(127.8)
Other comprehensive (loss) income before reclassifications			63	3.5
Amounts reclassified from accumulated other comprehensive (loss) income			0	0
Total other comprehensive income	46.2	3	63	3.5
Ending balance	(84.7)	(124.3)	(84.7)	(124.3)
(Losses) Gains from Hedging Activities
Changes in accumulated other comprehensive income (loss), net of tax
Beginning balance			0	0
Other comprehensive (loss) income before reclassifications			(0.7)	(1.2)
Amounts reclassified from accumulated other comprehensive (loss) income			0.6	1.1
Total other comprehensive income	0.5	(0.1)	(0.1)	(0.1)
Ending balance	(0.1)	(0.1)	(0.1)	(0.1)
Total
Changes in accumulated other comprehensive income (loss), net of tax
Beginning balance			(147.6)	(127.7)
Other comprehensive (loss) income before reclassifications			62	2.3
Amounts reclassified from accumulated other comprehensive (loss) income			0.6	0.6
Total other comprehensive income	46.4	2.9	62.6	2.9
Ending balance	$ (85)	$ (124.8)	$ (85)	$ (124.8)

Stock Incentive Plans - Narrati

Stock Incentive Plans - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	May 11, 2017	Feb. 03, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, par value (in usd per share)	$ 0.01		$ 0.01		$ 0.01		$ 0.01
Total cash and non-cash stock-based compensation cost			$ 2	$ 1.9	$ 7.7	$ 5.3
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, exercise price, percent of market value on the date of grant					100.00%
Stock option awards, contractual term					5 years
Award vesting period		3 years
Intrinsic value of all options exercised					$ 8.3
Unrecognized stock-based compensation expense for stock options			1.1		$ 1.1
Unrecognized stock-based compensation expense for stock options, period of recognition					1 year 12 days
Stock Option | Vesting 1, Year 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		33.33%
Stock Option | Vesting 1, Year 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		33.33%
Stock Option | Vesting 1, Year 3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		33.33%
Stock Option, 7 Year Grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards, contractual term		7 years
Stock Option, 10 Year Grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards, contractual term		10 years
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		3 years
Fully vested awards settled in shares					79,917
Fully vested awards settled in cash					$ 0.9
Awards granted (in shares)					95,000
Weighted average grant date fair value (in usd per share)					$ 26.42
Number of shares forfeited					84,000
Restricted Stock Units (RSUs) | Vesting 1, Year 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		33.33%
Restricted Stock Units (RSUs) | Vesting 1, Year 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		33.33%
Restricted Stock Units (RSUs) | Vesting 1, Year 3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		33.33%
Restricted Stock Units (RSUs) | Vesting 2, Year 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		0.00%
Restricted Stock Units (RSUs) | Vesting 2, Year 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		0.00%
Restricted Stock Units (RSUs) | Vesting 2, Year 3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		100.00%
Sign-On Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		2 years
Award vesting percentage		100.00%
Restricted Stock Units (RSUs) and Performance Based Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense for stock options, period of recognition					1 year 5 months
Total unrecognized compensation expense related to the RSU and PBU awards			$ 6.4		$ 6.4
2016 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock available for issuance			9,098,000		9,098,000
Number of shares repurchased					37,000	96,000
2016 Stock Incentive Plan | Performance Based Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period					3 years
2016 Stock Incentive Plan | Performance Based Units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected payout, percent of target					0.00%
2016 Stock Incentive Plan | Performance Based Units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected payout, percent of target					200.00%
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares registered	8,000,000
Fully vested awards settled in shares					100,000	100,000
2017 | 2016 Stock Incentive Plan | Performance Based Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)					165,974
Weighted average grant date fair value (in usd per share)					$ 26.48
Number of shares forfeited					13,257
2016 | 2016 Stock Incentive Plan | Performance Based Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in usd per share)					$ 17.04
Number of shares forfeited					35,505
Percent of units expected to settle in common stock			100.00%		100.00%

Stock Incentive Plans - Expense

Stock Incentive Plans - Expenses Related to Stock Options Granted, Valuation Assumptions (Details) - Stock Option	9 Months Ended
	Sep. 30, 2017$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	1.83%
Risk-free interest rate, maximum	2.10%
Volatility, minimum	31.42%
Volatility, maximum	31.96%
Dividend yield	0.00%
Average fair value per stock option (in usd per share)	$ 9.16
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average life of options (years)	5 years 6 months
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average life of options (years)	6 years 6 months

Stock Incentive Plans - Stock O

Stock Incentive Plans - Stock Option Activity (Details) - Stock Option - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Number Of Shares
Outstanding, beginning balance (in shares)	2,122
Options exercised (in shares)	493
Options forfeited/expired/canceled (in shares)	120
Options granted (in shares)	240
Outstanding, end balance (in shares)	1,749	2,122
Exercisable, end of period (in shares)	944
Weighted Average Exercise Price
Outstanding, beginning balance (in usd per share)	$ 16.92
Options exercised (in usd per share)	13.91
Options forfeited/expired/canceled (in usd per share)	19.64
Options granted (in usd per share)	26.48
Outstanding, ending balance (in usd per share)	18.90	$ 16.92
Exercisable, end of period (in usd per share)	$ 17.81
Other Disclosures
Outstanding, weighted-average remaining contractual term	3 years 6 months 18 days	3 years 6 months 26 days
Exercisable, weighted-average remaining contractual term	2 years 4 months 6 days
Outstanding, aggregated intrinsic value	$ 20,691	$ 20,748
Exercisable, aggregated intrinsic value	$ 12,190

Stock Incentive Plans - Restric

Stock Incentive Plans - Restricted Stock Units Award Activity (Details) - Restricted Stock Units (RSUs) shares in Thousands	9 Months Ended
	Sep. 30, 2017$ / sharesshares
Number Of Shares
Outstanding, beginning balance (in shares) | shares	538
RSUs settled (in shares) | shares	113
RSUs forfeited (in shares) | shares	84
RSUs granted (in shares) | shares	95
RSUs outstanding, ending balance (in shares) | shares	436
Weighted Average Grant Date Fair Value
Outstanding, beginning balance (in usd per share) | $ / shares	$ 17.22
RSUs settled (in usd per share) | $ / shares	17.23
RSUs forfeited (in used per share) | $ / shares	18.26
RSUs granted (in usd per share) | $ / shares	26.42
RSUs outstanding, ending balance (in usd per share) | $ / shares	$ 19.02

Stock Incentive Plans - Expecta

Stock Incentive Plans - Expectations of Future RSU Vesting and Settlement (Details) - Restricted Stock Units (RSUs) shares in Thousands	Sep. 30, 2017shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Vesting in 2017	20
Number of Shares Vesting in 2018	179
Number of Shares Vesting in 2019	212
Number of Shares Vesting in 2020	25
Settled in Cash in 2017	0.00%
Settled in Cash in 2018	11.00%
Settled in Cash in 2019	0.00%
Settled in Cash in 2020	0.00%
Settled in Stock in 2017	100.00%
Settled in Stock in 2018	89.00%
Settled in Stock in 2019	100.00%
Settled in Stock in 2020	100.00%

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Numerators
Net (loss) income from continuing operations attributable to GCP shareholders		$ (18.1)	$ 10.9	$ (41.8)	$ 33.2
Income from discontinued operations, net of income taxes		677.3	10.4	679.4	36.2
Net income attributable to GCP shareholders		$ 659.2	$ 21.3	$ 637.6	$ 69.4
Denominators
Weighted average common shares—basic calculation		71,600,000	71,000,000	71,200,000	70,800,000
Dilutive effect of employee stock awards (in shares)		0	1,200,000	0	800,000
Weighted average common shares—diluted calculation		71,600,000	72,200,000	71,200,000	71,600,000
Basic (loss) earnings per share
Net (loss) income from continuing operations attributable to GCP shareholders (in usd per share)		$ (0.25)	$ 0.15	$ (0.59)	$ 0.47
Income from discontinued operations, net of income taxes (in usd per share)		9.46	0.15	9.54	0.51
Net income attributable to GCP shareholders (in usd per share)	[1]	9.21	0.30	8.96	0.98
Diluted (loss) earnings per share
Net loss (income) from continuing operations attributable to GCP shareholders (in usd per share)	[2]	(0.25)	0.15	(0.59)	0.46
Income from discontinued operations, net of income taxes (in usd per share)	[2]	9.46	0.14	9.54	0.51
Net income attributable to GCP shareholders (in usd per share)	[1],[2]	$ 9.21	$ 0.30	$ 8.96	$ 0.97
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Treasury stock purchased				$ 1	$ 1.8
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, shares		0	0	0	100,000
Stock Option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, shares		100,000	0	100,000	200,000
2016 Stock Incentive Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Treasury stock purchased under GCP 2016 Stock Incentive Plan, shares				37,000	96,000
[1]	Amounts may not sum due to rounding
[2]	Dilutive effect only applicable to periods where there is net income from continuing operations.

Related Party Transactions an67

Related Party Transactions and Transactions with Grace - Related Party Expenses and Agreements (Details) - W.R. Grace & Co. - USD ($) $ in Millions	Feb. 03, 2016	Feb. 02, 2016	Sep. 30, 2017
Related Party Transaction [Line Items]
Allocated general corporate expenses		$ 2
Indemnified receivables, tax			$ 10.3
Indemnified payables, tax			$ 2.6
Maximum
Related Party Transaction [Line Items]
Transition period	18 months

Related Party Transactions an68

Related Party Transactions and Transactions with Grace - Parent Company Equity (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended		12 Months Ended
	Mar. 31, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Related Party Transaction [Line Items]
Total net transfers to parent			$ (672.2)
Transfers to parent, net, per Consolidated Statement of Cash Flows		$ 0	(758.7)
Distribution to Grace related to the Separation	$ 750	$ 750
W.R. Grace & Co.
Related Party Transaction [Line Items]
Total net transfers to parent			(672.2)
Other, net			(86.5)
Transfers to parent, net, per Consolidated Statement of Cash Flows			(758.7)
W.R. Grace & Co. | Cash pooling and general financing activities
Related Party Transaction [Line Items]
Total net transfers to parent			(685.1)
W.R. Grace & Co. | GCP expenses funded by parent
Related Party Transaction [Line Items]
Total net transfers to parent			6.6
W.R. Grace & Co. | Corporate costs allocations
Related Party Transaction [Line Items]
Total net transfers to parent			2
W.R. Grace & Co. | Provision for income taxes
Related Party Transaction [Line Items]
Total net transfers to parent			$ 4.3
W.R. Grace & Co. | Net pension liabilities
Related Party Transaction [Line Items]
Other, net				$ (44)
W.R. Grace & Co. | Fixed assets
Related Party Transaction [Line Items]
Other, net				(23)
W.R. Grace & Co. | Related party debt, deferred tax, and other
Related Party Transaction [Line Items]
Other, net				$ (36)

Operating Segment Information -

Operating Segment Information - Narrative (Details)	9 Months Ended
	Sep. 30, 2017segment
Segment Reporting [Abstract]
Number of operating segments	2

Operating Segment Information70

Operating Segment Information - Schedule of Operating Segment Data (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Net Sales
Net sales	$ 282.4	$ 263.4	$ 794.9	$ 785.1
Segment Operating Income
Operating income	45.8	48.8	125.1	142.6
Operating Segments
Segment Operating Income
Operating income	45.8	48.8	125.1	142.6
Operating Segments | Specialty Construction Chemicals
Net Sales
Net sales	156.2	162.8	449.1	466.6
Segment Operating Income
Operating income	15.7	23.2	44.5	53.7
Operating Segments | Specialty Building Materials
Net Sales
Net sales	126.2	100.6	345.8	318.5
Segment Operating Income
Operating income	$ 30.1	$ 25.6	$ 80.6	$ 88.9

Operating Segment Information71

Operating Segment Information - Reconciliation of Operating Segment Data to Financial Statements (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Operating income	$ 45.8	$ 48.8	$ 125.1	$ 142.6
Corporate costs	(76.3)	(67.4)	(221.9)	(199.5)
Loss on sale of product line			(2.1)	0
Currency and other financial losses in Venezuela			(40.1)	(2.9)
Restructuring expenses	(1.1)	(5.3)	(6.8)	(14.3)
Gain on termination and curtailment of pension and other postretirement plans			5.8	2.6
Net income attributable to noncontrolling interests	0.1	0.2	0.2	0.9
(Loss) income from continuing operations before income taxes	(32.5)	13.6	(37.9)	43.9
Operating Segments
Segment Reporting Information [Line Items]
Operating income	45.8	48.8	125.1	142.6
Corporate
Segment Reporting Information [Line Items]
Corporate costs	(7.5)	(9)	(28.9)	(29.1)
Corporate | Prior Segment - Darex
Segment Reporting Information [Line Items]
Corporate costs		(2.6)	5.4	7
Segment Reconciling Items
Segment Reporting Information [Line Items]
Certain pension costs	(2.1)	(1.8)	(7)	(5.4)
Loss on sale of product line	0	0	(2.1)	0
Currency and other financial losses in Venezuela	(36.7)	0	(39.1)	0
Litigation settlement	(4)	0	(4)	0
Pension MTM adjustment and other related costs, net	(3)	0	(2.9)	(2.7)
Gain on termination and curtailment of pension and other postretirement plans	0.8	0.2	5.9	2.6
Third-party and other acquisition-related costs	(2)	(0.3)	(5)	(0.3)
Amortization of acquired inventory fair value adjustment	(0.2)	0	(2.9)	0
Tax indemnification adjustments	0	0	(2.4)	0
Net income attributable to noncontrolling interests	0.1	0.2	0.2	0.9
Other financing costs	(6)	(1.2)	(6)	(1.2)
Interest expense, net	(14.5)	(17.6)	(49)	(47.8)
Segment Reconciling Items | Repositioning
Segment Reporting Information [Line Items]
Restructuring expenses	(1.1)	(5.3)	(6.8)	(14.3)
Segment Reconciling Items | Other plans
Segment Reporting Information [Line Items]
Restructuring expenses	$ (2.1)	$ (0.4)	$ (13)	$ (1.4)

Operating Segment Information72

Operating Segment Information - Geographic Area Data (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Net sales	$ 282.4	$ 263.4	$ 794.9	$ 785.1
Total North America
Segment Reporting Information [Line Items]
Net sales	141.5	128.6	396	378
United States
Segment Reporting Information [Line Items]
Net sales	132.5	119.6	374.2	353.1
Canada and Puerto Rico
Segment Reporting Information [Line Items]
Net sales	9	9	21.8	24.9
Europe Middle East Africa
Segment Reporting Information [Line Items]
Net sales	67	55.3	178.9	173.9
Asia Pacific
Segment Reporting Information [Line Items]
Net sales	58	61.3	168.4	180.9
Latin America
Segment Reporting Information [Line Items]
Net sales	$ 15.9	$ 18.2	$ 51.6	$ 52.3

Discontinued Operations - Narra

Discontinued Operations - Narrative (Details) - Darex - USD ($) $ in Millions	Jul. 03, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Disposed of by sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration to be received	$ 1,060
Term of Transition Services Agreement	24 months
Term of Master Tolling Agreement	24 months
Indemnification ayable		$ 5.7		$ 5.7
Pre-tax gain on sale of disposal group		883.7
Disposed of by sale | Other Liabilities
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Deferred consideration		68.7		68.7
Disposed of by sale | Minimum
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Term of delayed closings in non-U.S. jurisdictions	4 months
Disposed of by sale | Maximum
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Term of delayed closings in non-U.S. jurisdictions	27 months
Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Pre-tax gain on sale of disposal group		883.7	$ 0	883.7	$ 0
Provision (benefit) for income taxes		200	$ 7.1	199.7	$ 20
Unrecognized tax benefits		$ 31.2		$ 31.2

Discontinued Operations - Recon

Discontinued Operations - Reconciliation of Gain on Disposal (Details) - Darex - Disposed of by sale $ in Millions	3 Months Ended
	Sep. 30, 2017USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds included in gain recognized in third quarter of 2017	$ 1,000.2
Less: Transaction costs	15.9
Less: Net assets derecognized in third quarter of 2017	100.6
Gain recognized in third quarter of 2017 before income taxes	883.7
Less: Tax effect of gain recognized in third quarter of 2017	200
Gain recognized in third quarter of 2017 after income taxes	$ 683.7

Discontinued Operations - Incom

Discontinued Operations - Income (Loss) From Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income from discontinued operations, net of income taxes	$ 677.3	$ 10.4	$ 679.4	$ 36.2
Darex | Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales	9.1	79.1	156.9	237.8
Cost of goods sold	6	51.7	104.6	152.2
Selling, general and administrative expenses	6.6	8	40.1	24.1
Research and development expenses	0.1	1.2	2.3	3.5
Restructuring expenses	0.4	0	6.9	0
Gain on sale of business	(883.7)	0	(883.7)	0
Other non-operating expenses, net	2.4	0.7	7.5	1.8
Provision for income taxes	(200)	(7.1)	(199.7)	(20)
Less: Net income attributable to noncontrolling interests	0	0	(0.1)	0
Income from discontinued operations, net of income taxes	$ 677.3	$ 10.4	$ 679.4	$ 36.2

Discontinued Operations - Carry

Discontinued Operations - Carrying Amounts of Assets and Liabilities of Discontinued Operations (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash and cash equivalents	$ 0		$ 23.7
Current assets held for sale	16.8	$ 108
Noncurrent assets held for sale	2.5	55.4
Current liabilities held for sale	8.1	48.2
Noncurrent liabilities held for sale	0.3	20.9
Darex | Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash and cash equivalents	0	16.3
Trade accounts receivable	7.9	50.5
Inventories	7.9	32.3
Other current assets	1	8.9
Current assets held for sale	16.8	108
Properties and equipment, net	1.9	39.6
Goodwill	0	4.4
Technology and other intangible assets, net	0	0.4
Deferred income taxes	0	6.4
Other assets	0.6	4.6
Noncurrent assets held for sale	2.5	55.4
Accounts payable	6.8	26.7
Other current liabilities	1.3	21.5
Current liabilities held for sale	8.1	48.2
Deferred income taxes	0	2.3
Underfunded and unfunded defined benefit pension plans	0.3	14.8
Other liabilities	0	3.8
Noncurrent liabilities held for sale	$ 0.3	$ 20.9

Acquisitions - Narrative (Detai

Acquisitions - Narrative (Details) - USD ($) $ in Millions	May 17, 2017	Sep. 30, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill		$ 183.8	$ 114.9
Stirling Lloyd Plc
Business Acquisition [Line Items]
Percentage of voting interests acquired	100.00%
Total consideration transferred	$ 91.1
Cash acquired	16.1
Goodwill	$ 59.6
Goodwill impairment		$ 0.6

Acquisitions - Aggregate Purcha

Acquisitions - Aggregate Purchase Price Allocation (Details) - USD ($) $ in Millions	Sep. 30, 2017	May 17, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill	$ 183.8		$ 114.9
Stirling Lloyd Plc
Business Acquisition [Line Items]
Accounts receivable, net		$ 6.8
Other current assets		3.1
Inventories		4.2
Properties and equipment, net		3.4
Goodwill		59.6
Intangible assets		26.9
Accounts payable		(2.9)
Other current liabilities		(4.2)
Other liabilities		(5.8)
Net assets acquired		$ 91.1

Acquisitions - Intangible Asset

Acquisitions - Intangible Assets Acquired (Details) - Stirling Lloyd Plc $ in Millions	May 17, 2017USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 26.9
Customer Lists
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 15
Weighted-Average Amortization Period (in years)	10 years
Technology
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 9.8
Weighted-Average Amortization Period (in years)	11 years
Trademarks
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 2.1
Weighted-Average Amortization Period (in years)	10 years

Subsequent Event (Details)

Subsequent Event (Details) - Ductilcrete - Subsequent Event $ in Millions	Oct. 31, 2017USD ($)
Subsequent Event [Line Items]
Percentage of voting interests acquired	100.00%
Total consideration transferred	$ 32