EnPro Industries (NPO) 10-K 26 Feb 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 22, 2018	Jun. 30, 2017
Document Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Trading Symbol	NPO
Entity Registrant Name	ENPRO INDUSTRIES, INC
Entity Central Index Key	1,164,863
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		21,592,605
Entity Public Float			$ 1,497,015,868

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Net sales	$ 1,309.6	$ 1,187.7	$ 1,204.4
Cost of sales	865.2	793	808.9
Gross profit	444.4	394.7	395.5
Operating expenses:
Selling, general and administrative	326.3	303.8	302.8
Goodwill and other Intangible Asset Impairment	10.1	0	47
Asbestos settlement	0	80	0
Other	6.8	15.6	8.1
Total operating expenses	343.2	399.4	357.9
Operating income (loss)	101.2	(4.7)	37.6
Interest expense	(50.9)	(55.9)	(52.8)
Interest income	1.5	0.8	0.7
Gain on reconsolidation of GST and OldCo	534.4	0	0
Other expense, net	(8.7)	(8.9)	(4.1)
Income (loss) before income taxes	577.5	(68.7)	(18.6)
Income tax benefit (expense)	(37.7)	28.6	(2.3)
Net income (loss)	$ 539.8	$ (40.1)	$ (20.9)
Basic earnings per share:
Basic earnings (loss) per share	$ 25.28	$ (1.86)	$ (0.93)
Diluted earnings per share:
Diluted earnings (loss) per share	24.76	(1.86)	(0.93)
Cash dividends, Per Share	$ 0.88	$ 0.84	$ 0.80

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 539.8	$ (40.1)	$ (20.9)
Other comprehensive income (loss):
Foreign currency translation adjustments	14.4	(16.3)	(21.9)
Pension and post-retirement benefits adjustment (excluding amortization)	5.2	(7.8)	(3.4)
Amortization of pension and post-retirement benefits included in net income (loss)	7.7	6.9	7.1
Other comprehensive income (loss), before tax	27.3	(17.2)	(18.2)
Income tax benefit (expense) related to items of other comprehensive income (loss)	(4.8)	0.4	(1.8)
Other comprehensive income (loss), net of tax	22.5	(16.8)	(20)
Comprehensive income (loss)	$ 562.3	$ (56.9)	$ (40.9)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
OPERATING ACTIVITIES
Net income (loss)	$ 539.8	$ (40.1)	$ (20.9)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation	32.7	30.4	30.3
Amortization	31.1	26.7	27.8
Asset Impairments	12.1	0	47
Gain on reconsolidation of GST and OldCo	(534.4)	0	0
Asbestos settlement	0	80	0
Deferred income taxes	35.9	(30)	(1.1)
Stock-based compensation	9.5	5.1	4.1
Other non-cash adjustments	2.9	1.1	6.5
Asbestos liabilities	(95.5)	0	0
Asbestos insurance receivables	26.6	0	0
Change in assets and liabilities, net of effects of acquisitions, deconsolidation, and reconsolidation of businesses:
Accounts receivable, net	(35.7)	3	7.3
Inventories	7.9	2.4	(14.7)
Accounts payable	20.5	(2.9)	3.5
Other current assets and liabilities	(1.1)	8.4	19.3
Other non-current assets and liabilities	(5.7)	(19.6)	(22.6)
Net cash provided by operating activities	46.6	64.5	86.5
INVESTING ACTIVITIES
Purchases of property, plant and equipment	(41)	(35.8)	(36.8)
Payments for capitalized internal-use software	(3.7)	(4.1)	(4.6)
Proceeds from sale of business	0	6.6	0
Payments for acquisitions, net of cash acquired	(44.6)	(28.5)	(45.5)
Reconsolidation of GST and OldCo	41.1	0	0
Deconsolidation of OldCo	(4.8)	0	0
Capital Contribution to OldCo	(45.2)	0	0
Other	0.5	0.4	0.4
Net cash used in investing activities	(97.7)	(61.4)	(86.5)
FINANCING ACTIVITIES
Proceeds from debt	635.7	350.8	230.8
Repayments of debt	(484.3)	(278.1)	(189)
Repurchase of common stock	(11.5)	(30.4)	(85.3)
Dividends paid	(19)	(18.1)	(18)
Repurchase of convertible debentures conversion option	0	0	(21.6)
Other	(2.4)	(2.2)	(2.1)
Net cash provided by (used in) financing activities	118.5	22	(85.2)
Effect of exchange rate changes on cash and cash equivalents	10.4	(17)	(5.6)
Net increase (decrease) in cash and cash equivalents	77.8	8.1	(90.8)
Cash and cash equivalents at beginning of year	111.5	103.4	194.2
Cash and cash equivalents at end of year	189.3	111.5	103.4
Cash paid during the year for:
Interest	46.4	41	36.4
Income taxes	6.8	19.6	20.4
Non-cash Acquisitions of Property, Plant and Equipment	$ 7.2	$ 5.4	$ 5.7

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 189.3	$ 111.5
Accounts receivable, less allowance for doubtful accounts of $4.7 in 2017 and of $4.9 in 2016	261.7	208.1
Inventories	204.1	175.4
Income Tax Receivable	113.2	6.5
Prepaid expenses and other current assets	51.3	23.4
Total current assets	819.6	524.9
Property, plant and equipment, net	296.9	215.4
Goodwill	336.1	201.5
Other intangible assets, net	347	176.9
Investment in GST	0	236.9
Deferred income taxes and income tax receivable	24.8	152.6
Other assets	61.7	38.2
Total assets	1,886.1	1,546.4
Current liabilities
Short-term borrowings from GST	0	26.2
Notes payable to GST	0	12.7
Current maturities of long-term debt	0.2	0.2
Accounts payable	130.7	102.9
Asbestos liability	0.6	30
Accrued expenses	136.6	131
Total current liabilities	268.1	303
Long-term debt	618.3	424.8
Notes payable to GST	0	283.2
Asbestos Liability	0	80
Other liabilities	96.9	96.9
Total liabilities	983.3	1,187.9
Commitments and contingent liabilities
Shareholders’ equity
Common stock – $.01 par value; 100,000,000 shares authorized; issued 21,517,554 shares at December 31, 2017 and 21,558,145 shares at December 31, 2016	0.2	0.2
Additional paid-in capital	347.9	346.5
Retained earnings	604.4	84
Accumulated other comprehensive loss	(48.4)	(70.9)
Common stock held in treasury, at cost – 191,838 shares at December 31, 2017 and 194,073 shares at December 31, 2016	(1.3)	(1.3)
Total shareholders’ equity	902.8	358.5
Total liabilities and equity	$ 1,886.1	$ 1,546.4

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Accounts and notes receivable, allowance for doubtful accounts	$ 4.7	$ 4.9
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares, issued	21,517,554	21,558,145
Treasury stock, shares	191,838	194,073

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) shares in Millions, $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]
Balance, Shares at Dec. 31, 2014		24
Balance at Dec. 31, 2015	$ 459.8	$ 0.2	$ 372.5	$ 142.5	$ (54.1)	$ (1.3)
Net income (loss)	(20.9)			(20.9)
Other comprehensive income (loss)	(20)				(20)
Dividends	(18)			(18)
Repurchase of Convertible Debentures including call option settlement, Shares		(0.9)
Repurchase of Convertible Debentures, including call option settlement	(21.6)		(21.6)
Accretion of Convertible Debentures from temporary equity	1		1
Shares Repurchases, Shares		(1.3)
Shares Repurchases	(86)		(86)
Incentive plan activity, Shares		0.1
Incentive plan activity	1.5		1.8	(0.3)
Balance, Shares at Dec. 31, 2015		21.9
Balance at Dec. 31, 2014	623.8	$ 0.2	477.3	181.7	(34.1)	(1.3)
Balance at Dec. 31, 2016	358.5	$ 0.2	346.5	84	(70.9)	(1.3)
Net income (loss)	(40.1)			(40.1)
Other comprehensive income (loss)	(16.8)				(16.8)
Dividends	$ (18.1)			(18.1)
Shares Repurchases, Shares	(0.6)	(0.6)
Shares Repurchases	$ (29.7)		(29.7)
Incentive plan activity, Shares		0.1
Incentive plan activity	3.4		3.7	(0.3)		0
Balance, Shares at Dec. 31, 2016		21.4
Balance at Dec. 31, 2015	459.8	$ 0.2	372.5	142.5	(54.1)	(1.3)
Balance at Dec. 31, 2017	902.8	$ 0.2	347.9	604.4	(48.4)	(1.3)
Net income (loss)	539.8			539.8
Other comprehensive income (loss)	22.5				22.5
Dividends	$ (19.1)			(19.1)
Shares Repurchases, Shares	(0.2)	(0.2)
Shares Repurchases	$ (11.5)		(11.5)
Incentive plan activity, Shares		0.1
Incentive plan activity	10.4		10.4	0
Adoption of share-based payment accounting standard	0.2		0.5
Other	2		2
Balance, Shares at Dec. 31, 2017		21.3
Balance at Dec. 31, 2016	$ 358.5	$ 0.2	$ 346.5	$ 84	$ (70.9)	$ (1.3)

Overview, Basis of presentation

Overview, Basis of presentation, Significant Accounting Policies and Recently Issued Accounting Guidance	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Overview, Basis of Presentation, Significant Accounting Policies and Recently Issued Accounting Guidance	1. Overview, Basis of Presentation, Significant Accounting Policies and Recently Issued Accounting Guidance Overview EnPro Industries, Inc. (“we,” “us,” “our,” “EnPro” or the “Company”) is a leader in the design, development, manufacture and marketing of proprietary engineered industrial products that primarily include: sealing products; heavy-duty truck wheel-end component systems; self-lubricating, non-rolling bearing products; precision engineered components and lubrication systems for reciprocating compressors; and heavy-duty, medium-speed diesel, natural gas and dual fuel reciprocating engines, including parts and services. The term "Coltec" refers to our subsidiary Coltec Industries Inc prior to its merger with and into our OldCo, LLC subsidiary on December 31, 2016 and to its assigns and successor after such date. Basis of Presentation The Consolidated Financial Statements reflect the accounts of the Company and our majority-owned and controlled subsidiaries. All intercompany accounts and transactions between our consolidated operations have been eliminated. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America ("GAAP") requires management to make estimates and assumptions that affect the amounts of assets and liabilities and the disclosures regarding contingent assets and liabilities at period end and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. In the first quarter of 2017, we adopted a standard that was issued to modify and simplify several aspects of accounting for share-based payment transactions. Changes to the previous guidance primarily pertain to the income tax consequences of share-based payment transactions. Under the standard, all excess tax benefits and tax deficiencies (including tax benefits of dividends on share-based payment awards) are recognized as income tax expense or benefit in the income statement beginning in 2017. This adoption is made prospectively. Excess tax benefits/deficiencies recorded in income tax expense for the year ended December 31, 2017 were insignificant. We historically accounted for excess tax benefits in the Consolidated Statement of Cash Flows as a financing activity. Upon adoption of this standard, excess tax benefits are classified along with other income tax cash flows as an operating activity. We elected to adopt this portion of the standard on a prospective basis. Additionally, with respect to forfeitures of awards, we made the accounting policy election under the standard to account for forfeitures when they occur as opposed to estimating the number of awards that are expected to vest as of the grant date. This election was adopted under a modified retrospective transition method by means of a cumulative-effect adjustment to equity as of the beginning of 2017. As a result of this transition, a $0.3 million reduction was recorded to the 2017 opening retained earnings for this effect. Summary of Significant Accounting Policies Revenue Recognition – For the Sealing Products and Engineered Products segments, revenue is recognized at the time title and risk of product ownership is transferred or when services are rendered, typically when product is shipped or delivered, depending on the terms of the sale agreement. Shipping costs billed to customers are recognized as revenue and expensed in cost of goods sold since they are fixed and determinable and collection is reasonably assured. We generally use the percentage-of-completion (“POC”) accounting method to account for our long-term contracts associated with the design, development, manufacture, or modification of complex engines under fixed price or cost plus contracts. During the third quarter of 2011, the Power Systems segment began using POC for prospective engine contracts. We made this change because, as a result of enhancements to our financial management and reporting systems, we are able to reasonably estimate the revenue, costs, and progress towards completion of engine builds. If we are not able to meet those conditions for a particular engine contract, we recognize revenues using the completed-contract method. Additionally, engines that were in production at June 30, 2011 continued to use the completed-contract method through completion and shipment. Under POC, revenue is recognized based on the extent of progress towards completion of the long-term contract. We generally use the cost-to-cost measure for our long-term contracts unless we believe another method more clearly measures progress towards completion of the contract. Under the cost-to-cost measure, the extent of progress towards completion is measured based on the ratio of costs incurred to date to the total estimated costs at completion of the contract. Contract costs include labor, material and subcontracting costs, as well as an allocation of indirect costs. Revenues, including estimated fees or profits, are recorded as costs are incurred. Due to the nature of the work required to be performed on many of our contracts, the estimation of total revenue and cost at completion is complex and subject to many variables. Management must make assumptions and estimates regarding labor productivity including the benefits of learning and investments in new technologies, the complexity of the work to be performed, the availability and future prices of materials, the length of time to complete the contract (to estimate increases in wages and prices for materials and related support cost allocations), performance by our subcontractors and overhead cost rates, among other variables. Based on our analysis, any quarterly adjustments to net sales, cost of sales, and the related impact to operating income are recognized in the period they become known. These adjustments may result in an increase or a decrease in operating income. Changes in estimates of net sales, cost of sales, and the related impact to operating income are recognized quarterly on a cumulative catch-up basis, which recognizes in the current period the cumulative effect of the changes on current and prior periods based on a contract's percentage of completion. A significant change in one or more of these estimates could affect the profitability of one or more of our contracts. When estimates of total costs to be incurred on a contract exceed total estimates of revenue to be earned, a provision for the entire loss on the contract is recorded in the period the loss is determined. Contracts accounted for under the POC method represented revenues and margins of $76.3 million and $12.9 million , respectively, for the year ended December 31, 2017 , $86.3 million and $6.9 million , respectively, for the year ended December 31, 2016 , and $67.3 million and $8.9 million , respectively, for the year ended December 31, 2015 . Foreign Currency Translation – The financial statements of those operations whose functional currency is a foreign currency are translated into U.S. dollars using the current rate method. Under this method, all assets and liabilities are translated into U.S. dollars using current exchange rates, and income statement activities are translated using average exchange rates. The foreign currency translation adjustment is included in accumulated other comprehensive loss in the Consolidated Balance Sheets. Gains and losses on foreign currency transactions are included in operating income. Foreign currency transaction gains totaled $1.2 million , $ 1.5 million , and $1.8 million respectively, in 2017 and 2016 , and 2015 . Research and Development Expense – Costs related to research and development activities are expensed as incurred. We perform research and development primarily under Company-funded programs for commercial products. Research and development expenditures in 2017 , 2016 , and 2015 were $32.7 million , $28.9 million , and $22.5 million , respectively, and are included in selling, general and administrative expenses in the Consolidated Statements of Operations. Income Taxes – We use the asset and liability method of accounting for income taxes. Temporary differences arising between the tax basis of an asset or liability and its carrying amount on the Consolidated Balance Sheet are used to calculate future income tax assets or liabilities. This method also requires the recognition of deferred tax benefits, such as net operating loss carryforwards. A valuation allowance is recorded to reduce deferred tax assets when it is more likely than not that a tax benefit will not be realized. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to the taxable income (losses) in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the date of enactment of the change. A tax benefit from an uncertain tax position is recognized only if we believe it is more likely than not that the position will be sustained on its technical merits. If the recognition threshold for the tax position is met, only the portion of the tax benefit that we believe is greater than 50 percent likely to be realized is recorded. On December 22, 2017, the Tax Cuts and Jobs Act (the "Tax Act") was enacted and contains several key tax provisions impacting the Company including the reduction of the corporate income tax rate from 35.0% to 21.0% , the transition to a territorial tax system and a mandatory one-time transition tax on accumulated earnings of foreign subsidiaries. The impact of these tax law changes, including the remeasurement of our deferred tax assets and liabilities based on the tax rates in effect at the time the deferred balances are expected to reverse, the reassessment of the net realizability of the deferred tax balances, and the transition tax, are required to be recognized in our income tax provision in the fourth quarter 2017, the period of enactment. In December 2017, U.S. Securities and Exchange Commission ("SEC") issued guidance to address the application of authoritative tax accounting guidance in situations where companies do not have the necessary information available, prepared, or analyzed in reasonable detail to complete the accounting for certain income tax effects of the Tax Act for the reporting period in which the Tax Act was enacted. In these instances, the SEC's guidance allows us to record provisional amounts during a measurement period not to extend beyond one year of the enactment date. Since the Tax Act was passed at the end of 2017, and ongoing guidance and interpretation is expected over the next twelve months, we consider the impact of the transition tax, remeasurement of deferred tax assets and liabilities, and other items recorded in our year-end income tax provision to be a reasonable estimate, but provisional, subject to further analysis of year-end data and refinement of the Company’s calculations. We expect to complete our analysis within the one-year measurement period in accordance with the SEC's guidance. Please see Note 5, "Income Taxes" for further information on the provisional items recorded in 2017. Cash and Cash Equivalents – Cash and cash equivalents include cash on hand, demand deposits and highly liquid investments with a maturity of three months or less at the time of purchase. Receivables – Accounts receivable are stated at the historical carrying amount net of write-offs and allowance for doubtful accounts. We establish an allowance for doubtful accounts receivable based on historical experience and any specific customer collection issues we have identified. Doubtful accounts receivable are written off when a settlement is reached for an amount less than the outstanding historical balance or when we have determined the balance will not be collected. The balances billed but not paid by customers pursuant to retainage provisions in long-term contracts and programs are normally due upon completion of the contracts and/or acceptance by the owner of specified deliverables. At December 31, 2017 , we had $0.3 million of retentions expected to be collected in 2018 recorded in accounts receivable and $0.9 million of retentions expected to be collected beyond 2018 recorded in other long-term assets in the Consolidated Balance Sheet. At December 31, 2016 , we had $1.3 million of current retentions and $1.8 million of long-term retentions recorded in the Consolidated Balance Sheet. Inventories – Certain domestic inventories are valued by the last-in, first-out (“LIFO”) cost method. Inventories not valued by the LIFO method, other than inventoried costs relating to long-term contracts and programs, are valued using the first-in, first-out (“FIFO”) cost method, and are recorded at the lower of cost or net realizable value. Approximately 34% and 38% of inventories were valued by the LIFO method in 2017 and 2016 , respectively. Inventoried costs relating to long-term contracts and programs are stated at the actual production cost incurred to date, including direct labor and factory overhead. Progress payments related to long-term contracts and programs accounted for under the completed-contract method of accounting are shown as a reduction of inventories. Initial program start-up costs and other nonrecurring costs are expensed as incurred. Property, Plant and Equipment – Property, plant and equipment are recorded at cost. Depreciation of plant and equipment is determined on the straight-line method over the following estimated useful lives of the assets: buildings and improvements, 5 to 25 years; machinery and equipment, 3 to 10 years. Goodwill and Other Intangible Assets – Goodwill represents the excess of the purchase price over the estimated fair value of the net assets of acquired businesses, including the reconsolidated GST and OldCo businesses. Goodwill is not amortized, but instead is subject to annual impairment testing conducted each year as of October 1. The goodwill asset impairment test involves comparing the fair value of a reporting unit to its carrying amount. If the carrying amount of a reporting unit exceeds its fair value, a second step of comparing the implied fair value of the reporting unit’s goodwill to the carrying amount of that goodwill is required to measure the potential goodwill impairment loss. Interim tests may be required if an event occurs or circumstances change that would more likely than not reduce the fair value of a reporting unit below its carrying amount. We completed our required annual impairment tests of goodwill as of October 1, 2017 and 2016 . These assessments did not indicate any impairment of the goodwill, and the fair values of each of our reporting units significantly exceeded their carrying values. Through the first quarter of 2015, several initiatives were implemented to remove labor, facility and other costs from CPI’s cost structure and a customer-focused organizational realignment was implemented to identify price and volume opportunities to optimize sales and profitability in the weak oil and gas business environment. During the first quarter of 2015 new strategic options and opportunities to improve business performance were analyzed given the continuing weakness in demand. Additional strategic measures were planned to be implemented during the second half of 2015 and the expected benefits of these actions were taken into consideration in assessing the outlook for CPI. However, as more time passed, the benefits of strategic measures and initiatives being implemented were no longer expected to sufficiently compensate for the financial impacts of the prolonged and significant weakness in the oil and gas markets served by CPI. Taking this into account, the forecasted results for CPI were lowered significantly at the end of May 2015 to such an extent that we thought it likely that the fair value of CPI would be less than its carrying value which necessitated an interim impairment test for goodwill. The interim step one analysis we performed, using a combination of discounted cash flow and market value approaches to determine the fair value of CPI consistent with our annual impairment testing, indicated that the fair value of CPI was less than the carrying value of its net assets. The required step two valuation analysis performed as of May 31, 2015 and completed in July 2015 indicated that $ 46.1 million of the CPI goodwill balance was impaired. Accordingly, CPI goodwill in the amount of $ 46.1 million was written-off in the second quarter of 2015. We completed our required annual impairment test of goodwill as of October 1, 2017, which did not indicate any additional impairment of our goodwill. Other intangible assets are recorded at cost, or when acquired as a part of a business combination (including in the reconsolidation of GST and OldCo as it was treated as a business acquisition under applicable accounting rules), at estimated fair value. These assets include customer relationships, patents and other technology agreements, trademarks, licenses and non-compete agreements. Intangible assets that have definite lives are amortized using a method that reflects the pattern in which the economic benefits of the assets are consumed or the straight-line method over estimated useful lives of 2 to 21 years. Intangible assets with indefinite lives are subject to at least annual impairment testing, which compares the fair value of the intangible asset with its carrying amount using the relief from royalty method. Other than as described above, the results of our assessments did not indicate any impairment to our indefinite-lived intangible assets for the years presented. We review the carrying amounts of long-lived assets when certain events or changes in circumstances indicate that the carrying amounts may not be recoverable. In consideration of the poor financial performance of the ATDynamics business, an asset group in the Stemco division of our Sealing Products segment, for the quarter ended September 30, 2017 and significantly lowered expectations for the fourth quarter forecast and the budget for fiscal year 2018, we determined that a test of ATDynamics' recoverability was required. An impairment loss is recognized when the carrying amount of the asset group is not recoverable and exceeds its fair value. We estimate the fair values of assets subject to long-lived asset impairment based on our own judgments about the assumptions that market participants would use in pricing the assets. In doing so, we used an income approach based upon discounted cash flows. The key assumptions used for the discounted cash flow approach include expected cash flows based on internal business plans, projected growth rates, discount rates, and royalty rates for certain intangible assets. We classified these fair value measurements as Level 3. As a result of this test, certain of ATDynamics' definite-lived intangible assets were determined to be impaired, and were valued in total at $1.7 million , resulting in an impairment loss of $10.1 million , which equaled the excess of these assets' net book value at September 30, 2017 over their fair value. The loss is reflected in Goodwill and other intangible asset impairment in the Consolidated Statement of Operations. Additionally, during the year ended December 31, 2017, we determined that approximately $1.8 million of amortized customer relationship intangibles associated with certain smaller locations that we exited in 2017 would no longer provide continuing value to us as a result of the exits. Therefore, these assets were written off. As these write-offs relate to restructuring activities, this amount is presented in other operating expense in the Consolidated Statement of Operations for the year ended December 31, 2017. During the year ended December 31, 2015, we determined $0.9 million of amortized trademarks associated with CPI were impaired and therefore were written off. This amount is included in goodwill and other intangible asset impairment in the accompanying Consolidated Statement of Operations for the year ended December 31, 2015. Investment in GST – The historical business operations of Garlock Sealing Technologies LLC (“GST LLC”) and The Anchor Packing Company (“Anchor”) have resulted in a substantial volume of asbestos litigation in which plaintiffs have alleged personal injury or death as a result of exposure to asbestos fibers. Those subsidiaries manufactured and/or sold industrial sealing products, predominately gaskets and packing, that contained encapsulated asbestos fibers. Anchor was an inactive and insolvent indirect subsidiary. Our subsidiaries’ exposure to asbestos litigation and their relationships with insurance carriers have been managed through another Coltec subsidiary, Garrison Litigation Management Group, Ltd. (“Garrison”). GST LLC, Anchor and Garrison are collectively referred to as “GST.” On June 5, 2010 (the “GST Petition Date”), GST LLC, Anchor and Garrison filed voluntary petitions for reorganization under Chapter 11 of the United States Bankruptcy Code in the U.S. Bankruptcy Court for the Western District of North Carolina in Charlotte (the “Bankruptcy Court”). GST’s financial results were included in our consolidated results through June 4, 2010, the day prior to the GST Petition Date. However, GAAP requires that an entity that files for protection under the U.S. Bankruptcy Code, whether solvent or insolvent, whose financial statements were previously consolidated with those of its parent, as GST and its subsidiaries were with EnPro, generally must be prospectively deconsolidated from the parent and the investment accounted for using the cost method. At deconsolidation, our investment was recorded at its estimated fair value on June 4, 2010. The cost method required us to present our ownership interests in the net assets of GST at the GST Petition Date as an investment and to not recognize any income or loss from GST and subsidiaries in our results of operations during the reorganization period. During the pendency of these proceedings in the Bankruptcy Court, our investment in GST was subject to periodic reviews for impairment. When GST emerged from the supervision of the Bankruptcy Court upon confirmation and effectiveness of a plan of reorganization effective at 12:01 a.m. on July 31, 2017, the investment balance was derecognized as further described in Note 2, "Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC." Debt – Debt issuance costs associated with our 5.875% Senior Notes due in 2022 (the “Senior Notes”) that are incremental third party costs of issuing the debt are recognized as a reduction in the carrying value of the debt and amortized into interest expense over the time period to maturity using the interest method. Debt issuance costs associated with our senior secured revolving credit facility (the “Revolving Credit Facility”) are presented as an asset and subsequently amortized ratably over the term of the revolving debt arrangement. In October 2005, we issued $172.5 million in aggregate principal amount of 3.9375% Convertible Senior Debentures (the “Convertible Debentures”), which matured in October 2015. Applicable authoritative accounting guidance required that the liability component of the Convertible Debentures be recorded at its fair value as of the issuance date. This resulted in us recording debt in the amount of $111.2 million as of the issuance date with the $61.3 million offset to the debt discount being recorded in equity on a net of tax basis. The debt discount was amortized through interest expense until the maturity date of October 15, 2015, resulting in an effective interest rate of approximately 9.5% . Interest expense related to the Convertible Debentures for the year ended December 31, 2015 included $0.4 million of contractual interest coupon and $0.2 million of debt discount amortization. Derivative Instruments – We use derivative financial instruments to manage our exposure to various risks. The use of these financial instruments modifies the exposure with the intent of reducing our risk. We do not use financial instruments for trading purposes, nor do we use leveraged financial instruments. The counterparties to these contractual arrangements are major financial institutions. We use multiple financial institutions for derivative contracts to minimize the concentration of credit risk. The current accounting rules require derivative instruments, excluding certain contracts that are issued and held by a reporting entity that are both indexed to its own stock and classified in shareholders’ equity, be reported in the Consolidated Balance Sheets at fair value and that changes in a derivative’s fair value be recognized currently in earnings unless specific hedge accounting criteria are met. We are exposed to foreign currency risks that arise from normal business operations. These risks include the translation of local currency balances on our foreign subsidiaries’ balance sheets, intercompany loans with foreign subsidiaries and transactions denominated in foreign currencies. We strive to control our exposure to these risks through our normal operating activities and, where appropriate, through derivative instruments. We periodically enter into contracts to hedge forecasted transactions that are denominated in foreign currencies. The notional amount of foreign exchange contracts was $0.5 million and $2.8 million at December 31, 2017 and 2016 , respectively. All contracts outstanding at December 31, 2017 expired in January of 2018. The notional amounts of all of our foreign exchange contracts were recorded at their fair market value as of December 31, 2017 with changes in market value recorded in income. The earnings impact of any foreign exchange contract that is specifically related to the purchase of inventory is recorded in cost of sales and the changes in market value of all other contracts are recorded in selling, general and administrative expense in the Consolidated Statements of Operations. The balances of derivative assets are recorded in other current assets and the balances of derivative liabilities are recorded in accrued expenses in the Consolidated Balance Sheets. Fair Value Measurements – Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. We utilize a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three broad levels. The following is a brief description of those three levels: • Level 1: Observable inputs such as quoted prices in active markets for identical assets or liabilities. • Level 2: Inputs other than quoted prices that are observable for the asset or liability, either directly or indirectly. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. • Level 3: Unobservable inputs that reflect our own assumptions. The fair value of intangible assets associated with acquisitions was determined using a discounted cash flow analysis. Projecting discounted future cash flows required us to make significant estimates regarding future revenues and expenses, projected capital expenditures, changes in working capital and the appropriate discount rate. This non-recurring fair value measurement would be classified as Level 3 due to the absence of quoted market prices or observable inputs for assets of a similar nature. Similarly, the fair value computations for the recurring impairment analyses of goodwill and indefinite-lived intangible assets would be classified as Level 3 due to the absence of quoted market prices or observable inputs. The key assumptions used for the discounted cash flow approach include expected cash flows based on internal business plans, projected growth rates and discount rates. Significant changes in any of those inputs could result in a significantly different fair value measurement. Pensions and Post-retirement Benefits - Amortization of the net gain or loss resulting from experience different from that assumed and from changes in assumptions is included as a component of benefit cost. If, as of the beginning of the year, that net gain or loss exceeds 10% of the greater of the projected benefit obligation or the market-related value of plan assets, the amortization is that excess divided by the average remaining service period of participating employees expected to receive benefits under the plan. We amortize prior service cost using the straight-line basis over the average future service life of active participants. For segment reporting purposes, we allocate service cost and the amortization of prior service cost to each location generating those costs. All other components of net periodic pension cost are allocated based on each segment's projected benefit obligation. Recently Issued Accounting Guidance In February 2018, a standard was issued that helps organizations address certain stranded income tax effects in accumulated other comprehensive income resulting from the Tax Act. The standard provides financial statement preparers with an option to reclassify stranded tax effects within accumulated other comprehensive income to retained earnings in each period in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Act is recorded. The amendments in this guidance are effective for financial statements issued for interim and annual periods beginning after December 15, 2018, with early adoption permitted. We are currently evaluating the alternatives presented by the standard with respect to the tax effects associated with our pension plan unamortized net losses and service costs that are in our balance of accumulated other comprehensive income. In March 2017, a standard was issued that requires an employer to report the service cost component of pension and other postretirement benefits expense in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period. The other components of net benefit cost are required to be presented in the income statement separately from the service cost component and outside a subtotal of income from operations. The amendments in this standard also allow only the service cost component to be eligible for capitalization when applicable (for example, as a cost of internally manufactured inventory or a self-constructed asset). The standard is effective for fiscal years beginning after December 15, 2017, including interim periods within those annual periods, and is to be applied retrospectively for the classification of pension and other postretirement benefits expense on the income statement and prospectively for the criteria on capitalization of certain costs. For the years ended December 31, 2017 and 2016, the application of this guidance would have resulted in an increase in operating income of approximately $0.5 million and $2.2 million , respectively with a corresponding increase in non-operating expenses. In January 2017, a standard was issued to simplify annual and interim goodwill impairment testing for public business entities. Under the standard, an entity should perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. An entity still has the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. The standard is effective for any interim goodwill impairment tests in fiscal years beginning after December 15, 2019, and is to be applied prospectively. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The standard is not currently expected to have a significant impact on our consolidated financial statements or disclosures. In January 2017, a standard was issued to clarify the definition of a business in determining whether

Garlock Sealing Technologies LL

Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC	12 Months Ended
	Dec. 31, 2017
Reorganizations [Abstract]
Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC	2. Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC On the GST Petition Date, GST LLC filed voluntary petitions for reorganization under Chapter 11 of the United States Bankruptcy Code (the "GST Chapter 11 Case") in the Bankruptcy Court. The filings were the initial step in a claims resolution process for an efficient and permanent resolution of all pending and future asbestos claims through court approval of a plan of reorganization to establish a facility to resolve and pay all GST asbestos claims. On March 17, 2016, we announced that we had reached a comprehensive consensual settlement to resolve current and future asbestos claims which contemplated the joint plan of reorganization (the "Joint Plan") which was filed with the Bankruptcy Court. This settlement contemplated that Coltec would, subject to the receipt of necessary consents, undergo a corporate restructuring (the “Coltec Restructuring”) in which all of its significant operating assets and subsidiaries, which included each of the Company’s major business units, would be distributed to a new direct subsidiary of the Company, which would also assume all of Coltec’s non-asbestos liabilities. The Coltec Restructuring was completed on December 31, 2016, and included the merger of Coltec with and into OldCo, LLC (“OldCo”), an indirect subsidiary of EnPro. As further contemplated by the settlement, on January 30, 2017 (the "OldCo Petition Date"), OldCo filed a Chapter 11 bankruptcy petition with the Bankruptcy Court (the "OldCo Chapter 11 Case"). On February 3, 2017, the Bankruptcy Court issued an order for the joint administration of the OldCo Chapter 11 Case with the GST Chapter 11 Case. The Joint Plan was consummated on July 31, 2017. For more detail on the terms of the Joint Plan, see Note 20, "Subsidiary Asbestos Bankruptcies." During the pendency of the GST Chapter 11 Case and the related OldCo Chapter 11 Case, which are described further in Note 20, "Subsidiary Asbestos Bankruptcies," certain actions proposed to be taken by GST or OldCo not in the ordinary course of business were subject to approval by the Bankruptcy Court. As a result, during the pendency of the GST Chapter 11 Case and the OldCo Chapter 11 Case, we did not have exclusive control over these companies. Accordingly, as required by GAAP, GST was deconsolidated beginning on the GST Petition Date and OldCo was deconsolidated beginning on the OldCo Petition Date. Reconsolidation GST and OldCo were reconsolidated upon the effective date of the consummation of the Joint Plan, which effective date was 12:01 a.m. on July 31, 2017. The reconsolidation of GST and OldCo was treated as a business acquisition in accordance with applicable accounting rules. The primary businesses comprising GST will be managed as part of the Garlock division within our Sealing Products segment. Smaller businesses also reconsolidated with GST will be managed by the Technetics and Stemco divisions within this segment, by the CPI division within our Engineered Products segment, and by the Fairbanks Morse division, which comprises our Power Systems segment. The following table presents the preliminary fair value of the net assets of GST and OldCo acquired. The initial estimates reported at September 30, 2017 have been modified at December 31, 2017 due to an increase in the valuation of other assets by $7.1 million . These estimates remain subject to the final completion of the valuation process for GST and OldCo: (in millions) Accounts receivable $ 22.9 Inventories 29.2 Property, plant and equipment 63.2 Goodwill 125.5 Other intangible assets 180.8 Other assets 174.1 Liabilities assumed (110.5 ) Total purchase price $ 485.2 In accordance with GAAP, the purchase price for the acquisition was equal to the fair value of our investment in GST and OldCo on the reconsolidation date. In the reconsolidation, the investment in GST and OldCo is deemed to be exchanged for our exclusive control of these businesses. No cash is transferred in the reconsolidation transaction, other than the reconsolidation of GST's and OldCo's cash and cash equivalents at that date. The purchase price was allocated to the assets and liabilities reconsolidated with these businesses based on their estimated fair values. The excess of the purchase price over the identifiable assets acquired less the liabilities assumed was reflected as goodwill. Goodwill recorded as part of the purchase price allocation was $125.5 million , none of which is expected to be tax deductible given the nature of the transaction. See Note 10, "Goodwill and Other Intangible Assets" for information on goodwill by reportable segment from this transaction. The goodwill recognized in this transaction is primarily attributable to intangible assets that do not qualify for separate recognition. Identifiable intangible assets acquired as part of the acquisition were $180.8 million , including $40.4 million of indefinite-lived trade names and $140.4 million of definite-lived intangible assets. Definite-lived intangible assets included customer relationships of $85.4 million , proprietary technology of $50.8 million , and a favorable supply agreement valued at $4.2 million . The definite-lived intangible assets have an initial weighted average amortization period of 15 years for each class. Post-reconsolidation sales of $81.3 million and income before taxes of $6.5 million attributable to GST and OldCo are included in our Consolidated Statement of Operations for the year ended December 31, 2017. The following unaudited supplemental pro forma condensed consolidated financial results of operations for the Company for the years ended December 31, 2017 and 2016, are presented as if the reconsolidation had been completed on January 1, 2016: Years Ended December 31, 2017 2016 Pro forma net sales $ 1,402.5 $ 1,337.7 Pro forma net income $ 53.7 $ 520.0 Pro forma earnings per share - basic $ 2.52 $ 24.07 Pro forma earnings per share - diluted $ 2.46 $ 23.85 The 2017 supplemental pro forma net income was adjusted to exclude $4.1 million of pre-tax nonrecurring expenses related to the fair value adjustment to acquisition date inventory. The 2016 supplemental pro forma net income was adjusted to include these charges. Pro forma net income for the year ended December 31, 2016 also includes the gain on reconsolidation discussed further below, as well as the tax impact of the reconsolidation discussed in Note 5, "Income Taxes." The supplemental pro forma net income for the years ended December 31, 2017 and 2016 was also adjusted to exclude a combined $(16.7) million and $148.2 million , respectively, of non-recurring expenses (credits) associated with the aforementioned asbestos claims resolution process recorded at EnPro and at GST and OldCo, as the process is assumed to have concluded in order for the reconsolidation to occur. The amount adjusted for the year ended December 31, 2017 is inclusive of $24.7 million of credits for insurance reimbursements that became realizable for GST and OldCo in the current year. The amount adjusted for the year ended December 31, 2016 is inclusive of charges of $80.0 million and $49.5 million recorded by EnPro and GST, respectively, in that year in association with the Joint Plan to resolve current and future asbestos claims and the agreement with the Canadian provincial workers' compensation boards (the "Provincial Boards") resolving remedies the Provincial Boards may possess against Garlock of Canada Ltd, GST, Coltec or any of their affiliates. See Note 20, "Subsidiary Asbestos Bankruptcies." The remaining amount adjusted for each year consists of charges for Chapter 11 case-related fees and expenses including attorneys' and experts' fees and fees associated with the administration of Garrison. These unaudited supplemental pro forma financial results have been prepared for comparative purposes only. The pro forma information does not purport to be indicative of the results of operations that actually would have resulted had the reconsolidation occurred on January 1, 2016, or of future results of the consolidated entities. Associated with the reconsolidation of GST and OldCo, we recorded a pretax gain of $534.4 million . The amounts comprising the gain include: (in millions) Gain on revaluation of investment in GST and OldCo $ 248.3 Elimination of net amounts payable to GST and OldCo at reconsolidation date 286.1 Total $ 534.4 The gain on revaluation of our investment in GST and OldCo is the difference between the above-noted fair value of the investment and its book value of $236.9 million as of the date of reconsolidation. Although EnPro's investment in OldCo was negative at the time that it was deconsolidated from the EnPro results, EnPro Holdings had entered into a keep well agreement with OldCo under which it unconditionally agreed to make equity contributions to OldCo sufficient to maintain OldCo's ability to pay and discharge its liabilities as they become due and payable. As a result of this agreement, we recorded a liability on our Consolidated Balance sheet that represented this obligation related to our investment in OldCo. The portion of the gain attributable to elimination of net amounts payable to GST and OldCo is based upon the balances in EnPro's amounts due to and from GST and OldCo as of that date, including the notes payable to GST and related accrued interest, income tax receivable from GST, and other payables to and receivables from GST that arose in the normal course of business. 20. Subsidiary Asbestos Bankruptcies The historical business operations of certain of our subsidiaries, principally Garlock Sealing Technologies LLC (“GST LLC”) and The Anchor Packing Company (“Anchor”), had resulted in a substantial volume of asbestos litigation in which plaintiffs alleged personal injury or death as a result of exposure to asbestos fibers. On June 5, 2010 (the “GST Petition Date”), GST LLC, Anchor and another subsidiary, Garrison Litigation Management Group, Ltd. (“Garrison”), filed voluntary petitions for reorganization under Chapter 11 of the United States Bankruptcy Code (the “GST Chapter 11 Case”) in the U.S. Bankruptcy Court for the Western District of North Carolina in Charlotte (the “Bankruptcy Court”). GST LLC, Anchor and Garrison are sometimes referred to collectively as “GST” in this report. These filings were the initial step in a claims resolution process for an efficient and permanent resolution of pending and future asbestos claims through court approval of a plan of reorganization to establish a facility to resolve and pay all GST asbestos claims. The filings on the GST Petition Date did not include EnPro Industries, Inc. or any other EnPro Industries, Inc. operating subsidiary. GST LLC is one of the businesses in our broader Garlock group and, prior to the GST Petition Date, was included in our Sealing Products segment. GST LLC and its subsidiaries operate five manufacturing facilities, including operations in Palmyra, New York and Houston, Texas. The financial results of GST and subsidiaries were included in our consolidated results through June 4, 2010, the day prior to the GST Petition Date. However, U.S. generally accepted accounting principles (“GAAP”) require an entity that files for protection under the U.S. Bankruptcy Code, whether solvent or insolvent, whose financial statements were previously consolidated with those of its parent, as GST’s and its subsidiaries’ were with ours, generally must be prospectively deconsolidated from the parent and the investment accounted for using the cost method. At deconsolidation, our investment was recorded at its estimated fair value as of June 4, 2010, resulting in a gain for reporting purposes. The cost method required us to present our ownership interests in the net assets of GST at the GST Petition Date as an investment and we did not recognize any income or loss from GST and subsidiaries in our results of operations until the reconsolidation of these subsidiaries upon consummation of a plan of reorganization under these proceedings. In January 2015, we announced that GST and we had reached an agreement with the court-appointed representative of future asbestos claimants (the “GST FCR”) in the GST Chapter 11 Case that included a second amended plan of reorganization. The second amended plan was filed with the Bankruptcy Court on January 14, 2015 and superseded the prior reorganization plans filed by GST in the GST Chapter 11 Case. The GST FCR agreed to support, recommend and vote in favor of the second amended plan. The second amended plan would have provided for the establishment of two facilities - a settlement facility (which would receive $220 million from GST and $30 million from our then-consolidated Coltec Industries Inc subsidiary (“Coltec”) upon consummation of the second amended plan and additional contributions from GST aggregating $77.5 million over the seven years) and a litigation fund (which would receive $30 million from GST) to fund the defense and payment of claims of claimants who elect to pursue litigation under the second amended plan rather than accept the settlement option under the second amended plan. Funds contained in the settlement facility and the litigation fund would have provided the exclusive remedies for current and future GST asbestos claimants other than claimants whose claims had been resolved by settlement or verdict prior to the GST Petition Date and were not paid prior to the GST Petition Date. Under the terms of the second amended plan, we would have retained 100% of the equity interests of GST LLC. The second amended plan would have provided for the extinguishment of any derivative claims against us based on GST asbestos products and operations, but would not have protected us or our other subsidiaries, including Coltec, from non-derivative asbestos claims. In light of the filing of the second amended proposed plan of reorganization by GST on January 14, 2015, GST undertook to revise its estimate of ultimate costs to resolve all asbestos claims against it. Under the second amended plan, not less than $367.5 million would be required to fund the resolution of all GST asbestos claims, $30 million of which would be funded by Coltec. As a result, GST believed the low end of the range of values that would be necessary for it to resolve all present and future claims to be $337.5 million . Accordingly, GST revised its estimate of its ultimate asbestos expenditures to $337.5 million and had accrued its liability at December 31, 2015 at that amount and Coltec had accrued a liability of $30 million at December 31, 2015, which accrual was reflected in our consolidated financial results for 2015, in connection with its contribution to be made pursuant to the second amended plan. While the GST FCR had agreed to support the second amended plan of reorganization, the official committee representing current asbestos claimants (the “GST Committee”) in the GST Chapter 11 Case and their law firms opposed the second amended plan of reorganization. Accordingly, GST continued to seek a consensual resolution that would also be acceptable to representatives of current asbestos claimants as well as the GST FCR. On March 17, 2016, EnPro announced that it had reached a comprehensive settlement (the “Consensual Settlement”) to resolve current and future asbestos claims. The settlement was reached with the GST Committee and the GST FCR, and representatives for current and future asbestos claimants (the “Coltec Representatives”) against Coltec also joined in the settlement. Under the settlement, the GST Committee, the GST FCR and the Coltec Representatives agreed to join GST and Coltec in proposing a joint plan of reorganization (the “Joint Plan”) and to ask asbestos claimants and the court to approve the Joint Plan. The Joint Plan was filed with the Bankruptcy Court on May 20, 2016 and amendments to the Joint Plan were filed with the Bankruptcy Court on June 21, 2016, July 29, 2016, December 2, 2016, April 3, 2017, May 14, 2017, May 19, 2017, June 8, 2017, and June 9, 2017. As so modified, the Joint Plan superseded all prior plans of reorganization filed by GST with the Bankruptcy Court. Following receipt of all necessary asbestos claimant and judicial approvals, including approval by the United States District Court for the Western District of North Carolina (the “District Court”), the Joint Plan was consummated and became effective at 12:01 a.m. on July 31, 2017 (the “Joint Plan Effective Date”). The Joint Plan and Consensual Settlement contemplated that, as an appropriate and necessary step to facilitate the implementation of the Consensual Settlement and not to delay or hinder creditors or the resolution of claims, Coltec would, subject to the receipt of necessary consents, undergo a corporate restructuring (the “Coltec Restructuring”) in which all of its significant operating assets and subsidiaries, which included each of our major business units, would be distributed to a new direct EnPro subsidiary, EnPro Holdings, Inc. (“EnPro Holdings”). EnPro Holdings would also assume all of Coltec’s non-asbestos liabilities. The Coltec Restructuring was completed on December 31, 2016, and included the merger of Coltec with and into OldCo, LLC (“OldCo”), which was a direct subsidiary of EnPro Holdings. OldCo, as the restructured entity, retained responsibility for all asbestos claims and rights to certain insurance assets of Coltec, as well as the business operated by our EnPro Learning System, LLC subsidiary (“EnPro Learning System”), which provides occupational safety training and consulting services to third parties. EnPro Learning System was also merged into OldCo. As contemplated by the Joint Plan, on January 30, 2017 (the “OldCo Petition Date”), OldCo, as the successor by merger to Coltec, filed a Chapter 11 bankruptcy petition with the Bankruptcy Court (the “OldCo Chapter 11 Case”). On February 3, 2017, the Bankruptcy Court issued an order for the joint administration of the OldCo Chapter 11 Case with the GST Chapter 11 Case. As required by GAAP, OldCo was deconsolidated beginning on the OldCo Petition Date. Accordingly the financial results of OldCo and its subsidiaries were included in our consolidated results through January 29, 2017, the day prior to the OldCo Petition Date. Pursuant to the Joint Plan, a claims resolution trust (the “Trust”) was established prior to the Joint Plan Effective Date. As contemplated by the Joint Plan, the Trust was funded (i) with aggregate cash contributions by GST LLC and Garrison of $350 million made immediately prior to the Joint Plan Effective Date, (ii) by the contribution made by OldCo immediately prior to the Joint Plan Effective Date of $50 million in cash and an option (the “Option”), exercisable one year after the Joint Plan Effective Date, permitting the Trust to purchase for $1 shares of EnPro common stock having a value of $20 million (with OldCo having the right to call the Option for payment of $20 million in cash at any time prior to the first anniversary of the Joint Plan Effective Date, with the Trust having the right to put the Option to OldCo for payment by OldCo of $20 million on the day prior to the first anniversary of the Joint Plan Effective Date and with the Option terminating on the second anniversary of the Joint Plan Effective Date in return for payment to the Trust of $20 million ), and (iii) by the obligations under the Joint Plan of OldCo to make a deferred contribution of $60 million in cash and of GST LLC and Garrison to make an aggregate deferred contribution of $20 million in cash no later than one year after the Joint Plan Effective Date. These deferred contributions were guaranteed by EnPro and secured by a pledge of 50.1% of the outstanding voting equity interests of GST LLC and Garrison. The Consensual Settlement included as a condition to our obligations to proceed with the settlement that EnPro, Coltec, GST and Garlock of Canada Ltd (an indirect subsidiary of GST LLC) enter into a written agreement, to be consummated concurrently with the consummation of the Joint Plan on the Joint Plan Effective Date, with the Canadian provincial workers’ compensation boards (the “Provincial Boards”) resolving remedies the Provincial Boards may possess against Garlock of Canada Ltd, GST, Coltec or any of their affiliates, including releases and covenants not to sue, for any present or future asbestos-related claim, and that the agreement is either approved by the Bankruptcy Court following notice to interested parties or the Bankruptcy Court concludes that its approval is not required. On November 11, 2016, we entered into such an agreement (the “Canadian Settlement”) with the Provincial Boards to resolve current and future claims against EnPro, GST, Garrison, Coltec, and Garlock of Canada Ltd for recovery of a portion of amounts the Provincial Boards have paid and will pay in the future under asbestos-injury recovery statutes in Canada for claims relating to asbestos-containing products. The Canadian Settlement provides for an aggregate cash settlement payment to the Provincial Boards of $20 million (U.S.), payable on the fourth anniversary of the effective date of the Joint Plan. Under the Canadian Settlement, after the effective date of the Joint Plan, the Provincial Boards had the option of accelerating the payment, in which case the amount payable would be discounted from the fourth anniversary of the effective date of the Joint Plan to the payment date at a discount rate of 4.5% per annum. In return, the Provincial Boards have separately agreed to provide a covenant not to sue EnPro, any of EnPro’s affiliates or the Trust for any present or future asbestos-related claims. On February 3, 2017, the Bankruptcy Court issued an order approving the Canadian Settlement. Prior to the Joint Plan Effective Date, the Provincial Boards provided notice of their election to accelerate the payment. After application of the discount resulting from such acceleration of payment, the settlement payment of approximately $16.7 million (U.S.) was made to the Provincial Boards on August 11, 2017. In light of the Consensual Settlement and the Canadian Settlement, in 2016 GST further revised its estimate of the ultimate costs to resolve all asbestos claims against it. Under the Joint Plan proposed pursuant to the Consensual Settlement, $480 million was required to fund the resolution of all asbestos claims against GST and OldCo, as the successor by merger to Coltec, $370.0 million of which funded by GST LLC and Garrison and $110.0 million of which funded by OldCo. In addition, GST estimated the amount necessary to resolve all current and future Canadian asbestos claims alleging disease, resulting in whole or in part from exposure to GST asbestos-containing products, to be $17.0 million , the net present value of the amount to be paid pursuant to the Canadian Settlement. GST revised its estimate of its ultimate asbestos expenditures to $387.0 million and had accrued its liability at December 31, 2016 at that amount. In addition, OldCo (then still a consolidated subsidiary) had accrued a liability of $110.0 million at December 31, 2016 in connection with its contributions to be made pursuant to the Joint Plan, with the accrual of the $80.0 million increase in its estimated liability being reflected in our consolidated financial results for 2016. On November 29, 2017, GST LLC, EnPro Holdings and EnPro entered into an agreement with the Trust to provide for the early settlement of the deferred contributions to the Trust under the Joint Plan and for the call of the Option by EnPro Holdings, as the successor by merger to OldCo. Under that agreement, in full satisfaction of the $60 million of aggregate deferred contribution obligations under the Joint Plan and payment of the $20 million call payment under the Option, on December 1, 2017 GST LLC, EnPro Holdings and EnPro paid $78.8 million (the “Early Cash Settlement Amount”) to the Trust and agreed to make a further payment to the Trust to the extent that total interest earned through July 31, 2018, with respect to a fixed income account in which the Early Cash Settlement Amount was invested by the Trust is less than $1.2 million . The Joint Plan permanently resolves current and future asbestos claims against GST LLC, Garrison and OldCo, as the successor by merger to Coltec, and injunctions issued under the Joint Plan protect all of EnPro and its subsidiaries from those claims, which claims are enjoined under Section 524(g) of the U.S. Bankruptcy Code. Under the Joint Plan, the Trust has assumed responsibility for all present and future asbestos claims arising from the operations or products of GST LLC, Garrison or Coltec/OldCo. Under the Joint Plan, EnPro, through its subsidiaries, retained ownership of OldCo, GST LLC and Garrison. Anchor, which has not conducted business operations for many years and had nominal assets, has been dissolved.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2015
Business Combinations [Abstract]
Acquisitions	3. Acquisitions In October 2017, we acquired 100% of the stock of Commercial Vehicle Components Co., Ltd. ("CVC"), a manufacturer of air disc brake and medium duty hydraulic disc brake pads for the heavy-duty and medium-duty commercial vehicle aftermarket with annual revenues of approximately $1.5 million . CVC is managed as part of our Stemco division within the Sealing Products segment. In June 2017, we acquired certain assets and assumed certain liabilities of Qualiseal Technology (“Qualiseal”), a privately-held company offering custom-engineered mechanical face and circumferential seals for demanding aerospace and industrial applications with annual revenues of approximately $11 million . Qualiseal is managed as part of our Technetics division within the Sealing Products segment. The following table presents the purchase price allocation for acquisitions made in 2017: (in millions) Accounts receivable $ 1.6 Inventories 3.4 Property, plant and equipment 3.2 Goodwill 9.8 Other intangible assets 27.7 Other assets 0.2 Liabilities assumed (1.3 ) Total purchase price $ 44.6 In April 2016, we acquired certain assets and assumed certain liabilities of Rubber Fab Gasket & Molding, Inc. ("Rubber Fab"), a privately-held company offering a full range of high performance sanitary gaskets, hoses and fittings for the hygienic process industries. Rubber Fab is managed as part of EnPro’s Garlock division within the Sealing Products segment. We paid $22.6 million , net of cash acquired for this acquisition. In July 2015, we purchased the Veyance North American air spring business (the "Air Spring Business") through the purchase of 100% of the stock of Veyance's Mexico business and of all of the assets of its U.S. business. The Air Spring Business is a manufacturer of air springs that are used in the suspension systems of commercial vehicles. Following the acquisition, it became part of our Stemco division within the Sealing Products segment. The Air Spring Business manufactures products in its facility in San Luis Potosi, Mexico with a commercial organization in the U.S., Canada and Mexico, and engineering, testing and administrative resources in Fairlawn, Ohio. The addition of the Air Spring Business significantly expands Stemco's presence and scale in the commercial vehicle suspension market. In the second quarter of 2016, we finalized and agreed upon the acquisition date balance sheet of the Air Spring Business with the seller and made an additional cash payment of $5.9 million for the agreed-upon acquisition date working capital balance. In February 2015, we acquired 100% of the stock of ATDynamics, Inc. ("ATDynamics"), a privately-held company offering innovative aerodynamic products to the commercial trucking industry. ATDynamics is managed as part of our Stemco division within the Sealing Products segment. ATDynamics, with operations in Texas, is a leading designer and manufacturer of a suite of aerodynamic products engineered to reduce fuel consumption in the global freight transportation industry. We paid $ 45.5 million , net of cash acquired, in 2015 for the businesses acquired during that year. Because the assets, liabilities and results of operations for these acquisitions are not significant to our consolidated financial position or results of operations, pro forma financial information and additional disclosures are not presented.

Other Expense

Other Expense	12 Months Ended
	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Other Expense	4. Other Expense Operating We incurred $5.1 million , $13.4 million and $6.6 million of restructuring costs during the years ended December 31, 2017 , 2016 and 2015 , respectively. During 2017, we conducted a number of targeted restructuring activities throughout our operations, which included the exit of some smaller locations and targeted workforce reductions. All costs associated with such initiatives were incurred in 2017. Workforce reductions in 2017 associated with our restructuring activities totaled 117 administrative and manufacturing positions. During 2016, a company-wide initiative to reduce cost across all operating segments and the corporate office was initiated, which accounted for a substantial portion of the costs incurred for 2016. All costs associated with this initiative were incurred in 2016. Workforce reductions in 2016 associated with our restructuring activities, including the above plan and other smaller targeted activities, totaled 192 administrative and manufacturing positions. During 2015, we conducted a number of targeted restructuring activities throughout our operations, the most significant of which was at our CPI business. In October 2015, we approved a plan to restructure certain operations of our CPI unit in light of the prolonged and significant weakness in the markets served by CPI, particularly the oil and gas markets. In 2015 we incurred total expense related to the CPI restructuring plan of $3.8 million , including severance expense of $0.6 million , asset write-downs of $2.7 million , lease run-out costs of $0.1 million , and other associated costs of $0.4 million . These costs were incurred at our Engineered Products segment, and were reflected within other (operating) expense in our Consolidated Statements of Operations aside from inventory-related costs, which were reflected in cost of sales. The balance of the costs, $3.2 million , which consisted primarily of lease run-out costs, were recognized in 2016. Restructuring reserves at December 31, 2017 , as well as activity during the year, consisted of: Balance Provision Payments Balance (in millions) Personnel-related costs $ 3.5 $ 2.5 $ (5.3 ) $ 0.7 Facility relocation and closure costs 1.6 0.6 (1.0 ) 1.2 $ 5.1 $ 3.1 $ (6.3 ) $ 1.9 Also included in restructuring costs for 2017 were asset write-downs of approximately $2.0 million that did not affect the restructuring reserve liability. Restructuring reserves at December 31, 2016 , as well as activity during the year, consisted of: Balance Provision Payments Balance (in millions) Personnel-related costs $ 0.3 $ 8.3 $ (5.1 ) $ 3.5 Facility relocation and closure costs — 4.3 (2.7 ) 1.6 $ 0.3 $ 12.6 $ (7.8 ) $ 5.1 Also included in restructuring costs for 2016 were asset write-downs of approximately $0.8 million that did not affect the restructuring reserve liability. Restructuring reserves at December 31, 2015 , as well as activity during the year, consisted of: Balance, December 31, 2014 Provision Payments Balance (in millions) Personnel-related costs $ 1.1 $ 3.0 $ (3.8 ) $ 0.3 Facility relocation and closure costs 0.7 0.9 (1.6 ) — $ 1.8 $ 3.9 $ (5.4 ) $ 0.3 The above-mentioned asset write-downs at CPI did not affect the restructuring reserve liability. Restructuring costs by reportable segment are as follows: Years Ended December 31, 2017 2016 2015 (in millions) Sealing Products $ 3.6 $ 3.3 $ 0.4 Engineered Products 1.5 6.8 6.2 Power Systems — 0.4 — Corporate — 2.9 — $ 5.1 $ 13.4 $ 6.6 In consideration of the poor financial performance of the ATDynamics business, an asset group in the Stemco division of our Sealing Products segment, for the quarter ended September 30, 2017 and significantly lowered expectations for the fourth quarter forecast and the budget for fiscal year 2018, we performed a recoverability test, determining that the full value of certain definite-lived intangible assets was not recoverable. This assessment resulted in an impairment loss of $10.1 million in 2017. Refer to Note 14, "Fair Value Measurements" for further information about this assessment and the resulting loss. Also included in other operating expense for the years ended December 31, 2017 , 2016 and 2015 was $1.7 million , $2.2 million and $1.8 million , respectively, primarily consisting of legal fees related to the bankruptcy of certain subsidiaries discussed further in Note 2, "Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC". Non-Operating During 2017 , 2016 and 2015 , we recorded expense of $8.7 million , $8.6 million and $1.4 million , respectively, due to environmental reserve increases based on additional information at several specific sites of previously owned businesses. Refer to Note 21, "Commitments and Contingencies - Environmental" for additional information about our environmental liabilities. In 2016, we recorded a combined pre-tax loss of $0.4 million on the sale of all shares of our Franken Plastik business unit in the Sealing Products segment and our CPI Thailand business unit in the Engineered products segment. The Franken Plastik sale closed in late December, while the CPI Thailand sale closed in early June. We received $3.7 million for the sale of these businesses. The combined sales reported by the businesses were $7.3 million and $8.8 million for the years ended December 31, 2016 and 2015, respectively. Additional disclosures are not presented since the assets, liabilities and results of operations for these companies are not significant to our consolidated financial position or results of operations. In March 2015, we entered into privately negotiated transactions with certain holders of our Convertible Debentures to purchase the debentures. We recognized a $2.8 million pre-tax loss on the transaction.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	5. Income Taxes Income (loss) before income taxes as shown in the Consolidated Statements of Operations consists of the following: Years Ended December 31, 2017 2016 2015 (in millions) Domestic $ 524.1 $ (96.4 ) $ (3.0 ) Foreign 53.4 27.7 (15.6 ) Total $ 577.5 $ (68.7 ) $ (18.6 ) A summary of income tax benefit (expense) in the Consolidated Statements of Operations is as follows: Years Ended December 31, 2017 2016 2015 (in millions) Current: Federal $ (15.6 ) $ (8.7 ) $ (4.0 ) Foreign 17.6 10.6 9.8 State (0.2 ) (0.5 ) (2.4 ) 1.8 1.4 3.4 Deferred: Federal 14.4 (25.5 ) 3.6 Foreign 17.0 0.2 (6.0 ) State 4.5 (4.7 ) 1.3 35.9 (30.0 ) (1.1 ) Total $ 37.7 $ (28.6 ) $ 2.3 On December 22, 2017, the Tax Act was enacted and contains several key tax provisions impacting the Company including the reduction of the corporate income tax rate from 35.0% to 21.0% , the transition to a territorial tax system and a mandatory one-time transition tax on accumulated earnings of foreign subsidiaries. The impact of these tax law changes, including the remeasurement of our deferred tax assets and liabilities based on the tax rates in effect at the time the deferred balances are expected to reverse, the reassessment of the net realizability of the deferred tax balances, and the transition tax, are required to be recognized in our income tax provision in the fourth quarter 2017, the period of enactment. In December 2017, U.S. Securities and Exchange Commission ("SEC") issued guidance to address the application of authoritative tax accounting guidance in situations where companies do not have the necessary information available, prepared, or analyzed in reasonable detail to complete the accounting for certain income tax effects of the Tax Act for the reporting period in which the Tax Act was enacted. In these instances, the SEC's guidance allows us to record provisional amounts during a measurement period not to extend beyond one year of the enactment date. Since the Tax Act was enacted at the end of 2017 and ongoing guidance and interpretation is expected in the next several months, we have recorded a provisional estimate in our fourth quarter 2017 income tax provision relating to the impact of the transition tax, remeasurement of the deferred tax assets and liabilities, and tax planning strategies. We consider this to be a reasonable estimate and will continue to refine our calculations based on further analysis of final year-end data, including our accumulated foreign earnings and foreign cash balances, and review of forthcoming guidance and interpretation. We expect to complete our analysis within the one-year measurement period permitted in the guidance issued by the SEC. Income tax benefits recorded directly to additional paid-in capital consisted of the following: Years Ended December 31, 2017 2016 2015 (in millions) Stock options exercised and restricted stock units vested $ — $ — $ (1.8 ) $ — $ — $ (1.8 ) Significant components of deferred income tax assets and liabilities at December 31, 2017 and 2016 are as follows: 2017 2016 (in millions) Deferred income tax assets: Net operating losses and tax credits $ 89.6 $ 13.8 Accrual for post-retirement benefits other than pensions 4.1 4.5 Environmental reserves 6.5 8.7 Retained liabilities of previously owned businesses 1.2 2.1 Accruals and reserves 6.2 8.7 Pension obligations — 10.2 Inventories 2.5 5.1 Asbestos settlement — 41.4 Interest 12.0 9.9 Compensation and benefits 5.2 10.8 Gross deferred income tax assets 127.3 115.2 Valuation allowance (25.7 ) (20.2 ) Total deferred income tax assets 101.6 95.0 Deferred income tax liabilities: Depreciation and amortization (86.6 ) (44.2 ) GST deconsolidation gain — (21.4 ) Joint ventures and partnerships (0.3 ) — Asbestos settlement (6.3 ) — Pension obligations (1.7 ) — Total deferred income tax liabilities (94.9 ) (65.6 ) Net deferred tax assets $ 6.7 $ 29.4 We offset deferred tax assets and liabilities against one another only to the extent they relate to the same tax jurisdiction. If this condition is not satisfied, the balances are classified independently on the balance sheet. In 2015, we adopted authoritative guidance that simplifies the presentation of deferred income taxes through requiring all deferred tax liabilities and assets be classified as noncurrent in a classified balance sheet. At December 31, 2017, in accordance with the Tax Act, we remeasured our U.S. deferred tax assets and liabilities from the tax rate of 35.0% to 21.0% . This remeasurement resulted in a $35.0 million provisional net reduction in deferred tax liabilities. The net deferred tax assets are reflected on the December 31, 2017 and 2016 Consolidated Balance Sheets as follows: 2017 2016 (in millions) Deferred income taxes and income tax receivable $ 24.8 $ 33.6 Other liabilities (non-current) (18.1 ) (4.2 ) Net deferred tax assets $ 6.7 $ 29.4 At December 31, 2017 , we had $47.6 million of foreign net operating loss carryforwards (tax effect of $12.8 million ) of which $17.6 million expire at various dates beginning in 2018 , and $30.0 million have an indefinite carryforward period. We also had state net operating loss carryforwards with a tax effect of $17.0 million which expire at various dates between 2018 through 2037 . These net operating loss carryforwards may be used to offset a portion of future taxable income and, thereby, reduce or eliminate our U.S. federal, state or foreign income taxes otherwise payable. As a result of the ten -year carryback of our 2017 net operating tax loss generated by the funding of the Trust (as described in Note 20, "Subsidiary Asbestos Bankruptcies"), $3.2 million of foreign tax credits previously utilized during the carryback period will be available to offset our future tax liability. In addition, foreign tax credits of $43.5 million generated as a result of the transition tax will also be available to offset our future tax liability. These foreign tax credits expire in years 2018 through 2027 and based on our projected foreign source income, are expected to be fully utilized. We determined, based on the available evidence, that it is uncertain whether future taxable income of certain of our foreign subsidiaries will be significant enough or of the correct character to recognize certain of these deferred tax assets. As a result, valuation allowances of $25.7 million and $20.2 million have been recorded as of December 31, 2017 and 2016 , respectively. Valuation allowances primarily relate to certain state and foreign net operating losses and other net deferred tax assets in jurisdictions where future taxable income is uncertain. Valuation allowances may arise associated with deferred tax assets recorded in purchase accounting. In accordance with applicable accounting guidelines, any reversal of a valuation allowance that was recorded in purchase accounting reduces income tax expense. The effective income tax rate from operations varied from the statutory federal income tax rate as follows: Percent of Pretax Income Years Ended December 31, 2017 2016 2015 Statutory federal income tax rate 35.0 % 35.0 % 35.0 % U.S. taxation of foreign profits, net of foreign tax credits 0.1 1.1 1.1 Research and employment tax credits (0.4 ) 3.2 7.7 State and local taxes 0.2 4.9 4.1 Domestic production activities (0.4 ) 1.8 5.5 Nondeductible goodwill impairment — — (48.6 ) Foreign tax rate differences (1.0 ) 4.3 (10.2 ) Uncertain tax positions (0.1 ) (1.4 ) 4.3 Statutory changes in tax rates 0.3 0.2 1.4 Valuation allowance 0.2 (6.7 ) (2.1 ) Nondeductible expenses 0.3 (1.1 ) (6.6 ) Gain on reconsolidation of GST and OldCo (32.4 ) — — Reconsolidation step-up of net assets of GST and OldCo to fair value 9.0 — — Tax Act (5.3 ) — — Other items, net 1.0 0.4 (3.9 ) Effective income tax rate 6.5 % 41.7 % (12.3 )% The effect of the Tax Act resulted in a $30.9 million provisional net benefit recorded to income tax expense in the fourth quarter. This provisional amount represents a reasonable estimate of the impact and is comprised of a $35.0 million provisional tax benefit related to the remeasurement of deferred tax assets and liabilities, a $53.9 million provisional tax charge for the mandatory one-time transition tax on accumulated earnings of our foreign subsidiaries, and a $43.5 million provisional tax benefit for foreign tax credits related to the transition tax that will be utilized against our future tax liability due to the current year tax loss generated by the funding of the Trust. As a result of the Tax Act, we also implemented tax planning strategies in the fourth quarter of 2017 resulting in an additional provisional tax benefit of $6.3 million . We have not provided for the federal and foreign withholding taxes on approximately $447 million of foreign subsidiaries’ undistributed earnings as of December 31, 2017 , because such earnings are intended to be reinvested indefinitely. Upon repatriation, certain foreign countries impose withholding taxes. The amount of withholding tax that would be payable on remittance of the entire amount would be approximately $5.4 million . Although such earnings are intended to be reinvested indefinitely, any tax liability for withholding taxes would be negated by the availability of corresponding foreign tax credits. As a result of the mandatory one-time transition tax on accumulated foreign earnings imposed by the Tax Act, we are re-evaluating our repatriation policy as earnings of our foreign subsidiaries will be available for repatriation without incremental U.S. taxes. However, we have not yet made any changes to our repatriation policy. As of December 31, 2017 and 2016 , we had $3.8 million and $2.8 million , respectively, of gross unrecognized tax benefits. Of the gross unrecognized tax benefit balances as of December 31, 2017 and 2016 , $3.8 million and $2.8 million , respectively, would have an impact on our effective tax rate if ultimately recognized. We record interest and penalties related to unrecognized tax benefits in income tax expense. In addition to the gross unrecognized tax benefits above, we had $0.2 million and $0.2 million accrued for interest and penalties at December 31, 2017 and 2016 , respectively. Income tax expense for the year ended December 31, 2017 was not affected by interest and penalties related to unrecognized tax benefits. Income tax expense for the years ended December 31, 2016 and 2015 , includes $0.1 million and $0.1 million , respectively, for interest and penalties related to unrecognized tax benefits. The amounts listed above for accrued interest do not reflect the benefit of any tax deduction, which might be available if the interest were ultimately paid. A reconciliation of the beginning and ending amount of the gross unrecognized tax benefits (excluding interest) is as follows: (in millions) 2017 2016 2015 Balance at beginning of year $ 2.8 $ 1.5 $ 3.1 Reconsolidation of GST and OldCo 0.2 — — Additions based on tax positions related to the current year 0.3 0.4 0.3 Additions for tax positions of prior years 1.1 1.1 0.2 Reductions as a result of a lapse in the statute of limitations (0.3 ) (0.2 ) (2.0 ) Reductions as a result of audit settlements (0.3 ) — — Changes due to fluctuations in foreign currency — — (0.1 ) Balance at end of year $ 3.8 $ 2.8 $ 1.5 U.S. federal income tax returns after 2013 remain open to examination. In June 2017, the U.S. Internal Revenue Service (“IRS”) began an examination of our 2014 U.S. federal income tax return. Although this examination is part of a routine and recurring cycle, we cannot predict the final outcome or expected conclusion date of the audit. We and our subsidiaries are also subject to income tax in multiple state and foreign jurisdictions. Various foreign and state tax returns are also currently under examination. The most significant of these include France and Germany. Substantially all significant state, local and foreign income tax returns for the years 2013 and forward are open to examination. We expect that some of these examinations may conclude within the next twelve months, however, the final outcomes are not yet determinable. If these examinations are concluded or effectively settled within the next twelve months, it could reduce the associated gross unrecognized tax benefits by approximately $1.0 million . In addition, another $ 0.7 million in gross unrecognized tax benefits may be recognized within the next twelve months as the applicable statute of limitations expires.

Earnings (Loss) Per Share

Earnings (Loss) Per Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings (Loss) Per Share	6. Earnings (Loss) Per Share Basic earnings (loss) per share is computed by dividing the net income (loss) by the applicable weighted-average number of common shares outstanding for the period. Diluted earnings (loss) per share is calculated using the weighted-average number of shares of common stock as adjusted for any potentially dilutive shares as of the balance sheet date. The computation of basic and diluted earnings per share is as follows (in millions, except per share data): 2017 2016 2015 Numerator (basic and diluted): Net income (loss) $ 539.8 $ (40.1 ) $ (20.9 ) Denominator: Weighted-average shares – basic 21.3 21.6 22.5 Share-based awards 0.5 — — Weighted-average shares – diluted 21.8 21.6 22.5 Earnings (loss) per share: Basic $ 25.28 $ (1.86 ) $ (0.93 ) Diluted $ 24.76 $ (1.86 ) $ (0.93 ) In the years ended December 31, 2016 and December 31, 2015, there was a loss attributable to common shares. There were 0.2 million and 0.8 million , respectively of potentially dilutive shares excluded from the calculation of diluted earnings per share during those periods since they were antidilutive.

Inventories

Inventories	12 Months Ended
	Dec. 31, 2017
Inventory Disclosure [Abstract]
Inventories	7. Inventories As of December 31, 2017 2016 (in millions) Finished products $ 121.4 $ 108.1 Work in process 33.0 23.7 Raw materials and supplies 59.2 49.3 213.6 181.1 Reserve to reduce certain inventories to LIFO basis (10.2 ) (12.1 ) Manufacturing inventories 203.4 169.0 Incurred costs related to long-term contracts 0.7 13.6 Progress payments related to long-term contracts — (7.2 ) Net balance associated with completed-contract inventories 0.7 6.4 Total inventories $ 204.1 $ 175.4 Incurred costs related to long-term contracts in the table above represent inventoried work in process and finished products related to engine contracts accounted for under the completed-contract method, where costs incurred exceed customer billings. Refer to Note 8, “Long-Term Contracts” for additional information about incurred costs and progress payments related to long-term contracts.

Long-Term Contracts

Long-Term Contracts	12 Months Ended
	Dec. 31, 2017
Contractors [Abstract]
Long-Term Contracts	8. Long-Term Contracts See Note 1, "Revenue Recognition" for information regarding engine contracts accounted for under the POC method. Additional information regarding engine contracts accounted for under the POC method is as follows: As of December 31, 2017 2016 (in millions) Cumulative revenues recognized on uncompleted POC contracts $ 348.2 $ 260.7 Cumulative billings on uncompleted POC contracts 300.7 231.6 $ 47.5 $ 29.1 These amounts were included in the accompanying Consolidated Balance Sheets under the following captions: As of December 31, 2017 2016 (in millions) Accounts receivable (POC revenue recognized in excess of billings) $ 51.7 $ 31.4 Accrued expenses (billings in excess of POC revenue recognized) (4.2 ) (2.3 ) $ 47.5 $ 29.1 Additional information regarding engine contracts accounted for under the completed-contract method is as follows: As of December 31, 2017 2016 (in millions) Incurred costs relating to long-term contracts $ — $ 0.1 Progress payments related to long-term contracts — (1.0 ) Net balance associated with completed-contract inventories $ — $ (0.9 ) Incurred costs related to long-term contracts in the table above represent inventoried work in process and finished products related to engine contracts accounted for under the completed-contract method, where customer billings exceed costs incurred. Progress payments related to long-term contracts in the table above are either advanced billings or milestone billings to the customer on contracts accounted for under the completed-contract method. Upon shipment of the completed engine, revenue associated with the engine is recognized, and the incurred inventoried costs and progress payments are relieved. At December 31, 2016 , progress payments related to long-term contracts shown above were in excess of incurred costs resulting in a net liability balance. As such, the net liability balance is reflected in accrued expenses in the accompanying Consolidated Balance Sheet. Refer to Note 7, “Inventories” for additional information about incurred costs and progress payments related to long-term contracts for which the incurred costs exceeded the progress payments. In addition to inventoried costs, we also make deposits and progress payments to certain vendors for long lead time manufactured components associated with engine projects. At December 31, 2017 and 2016 , deposits and progress payments for long lead time components totaled $2.9 million and $0.8 million . These deposits and progress payments are classified in prepaid expenses and other current assets in the accompanying Consolidated Balance Sheets.

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	9. Property, Plant and Equipment As of December 31, 2017 2016 (in millions) Land $ 13.9 $ 11.0 Buildings and improvements 141.5 112.8 Machinery and equipment 448.7 367.8 Construction in progress 31.9 31.2 636.0 522.8 Less accumulated depreciation (339.1 ) (307.4 ) Total $ 296.9 $ 215.4

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	10. Goodwill and Other Intangible Assets The changes in the net carrying value of goodwill by reportable segment for the years ended December 31, 2017 and 2016 are as follows: Sealing Products Engineered Products Power Systems Total (in millions) Goodwill as of December 31, 2015 $ 179.7 $ 9.1 $ 7.1 $ 195.9 Foreign currency translation (1.5 ) — — (1.5 ) Sale of businesses (0.7 ) — — (0.7 ) Acquisitions 7.8 — — 7.8 Goodwill as of December 31, 2016 185.3 9.1 7.1 201.5 Foreign currency translation (0.7 ) — — (0.7 ) Acquisitions 9.8 — — 9.8 Reconsolidation of GST and OldCo 118.8 1.8 4.9 125.5 Goodwill as of December 31, 2017 $ 313.2 $ 10.9 $ 12.0 $ 336.1 The goodwill balances reflected above are net of accumulated impairment losses of $27.8 million for the Sealing Products segment as of December 31, 2017 , 2016 and 2015 and $154.8 million for the Engineered Products segment as of December 31, 2017 and 2016 , and 2015 . Identifiable intangible assets are as follows: As of December 31, 2017 As of December 31, 2016 Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated Amortization (in millions) Amortized: Customer relationships $ 311.2 $ 138.0 $ 216.2 $ 122.0 Existing technology 113.0 37.5 63.0 31.0 Trademarks 35.8 22.3 35.4 19.6 Other 28.7 23.2 23.2 22.1 488.7 221.0 337.8 194.7 Indefinite-Lived: Trademarks 79.3 — 33.8 — Total $ 568.0 $ 221.0 $ 371.6 $ 194.7 Amortization expense for the years ended December 31, 2017 , 2016 and 2015 was $24.7 million , $21.0 million and $21.9 million , respectively. The estimated amortization expense for those intangible assets for the next five years is as follows (in millions): 2018 $ 29.8 2019 $ 29.1 2020 $ 28.7 2021 $ 26.3 2022 $ 20.9

Accrued Expenses

Accrued Expenses	12 Months Ended
	Dec. 31, 2017
Payables and Accruals [Abstract]
Accrued Expenses	11. Accrued Expenses As of December 31, 2017 2016 (in millions) Salaries, wages and employee benefits $ 63.7 $ 40.0 Interest 8.6 38.1 Customer advances 7.1 5.3 Income and other taxes 14.3 11.2 Other 42.9 36.4 $ 136.6 $ 131.0

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2017
Related Party Transactions [Abstract]
Related Party Transactions	12. Related Party Transactions On the GST Petition Date, GST commenced an asbestos claims resolution process under Chapter 11 of the United States Bankruptcy Code. The resulting deconsolidation of GST from our financial results, discussed more fully in Note 2, "Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC", required certain intercompany indebtedness described below to be reflected on our Consolidated Balance Sheets. As of December 31, 2016, Coltec Finance Company Ltd., a wholly-owned subsidiary of Coltec, had aggregate, short-term borrowings of $26.2 million from GST’s subsidiaries in Mexico and Australia. These unsecured obligations were denominated in the currency of the lending party, and bore interest based on the applicable one-month interbank offered rate for each foreign currency involved. With the reconsolidation of GST in the third quarter, these borrowings are now intercompany and are therefore not reflected on our Consolidated Balance Sheet as of December 31, 2017. Effective as of January 1, 2010, Coltec entered into an original issue amount $73.4 million Amended and Restated Promissory Note due January 1, 2017 (the “Coltec Note”) in favor of GST LLC, and our subsidiary Stemco LP entered into an original issue amount $153.8 million Amended and Restated Promissory Note due January 1, 2018, in favor of GST LLC (the “Stemco Note”, and together with the Coltec Note, the “Notes Payable to GST”). The Notes Payable to GST amended and replaced promissory notes in the same principal amounts which were initially issued in March 2005, and which expired on January 1, 2010. The Notes Payable to GST bear interest at 11% per annum, of which 6.5% is payable in cash and 4.5% is added to the principal amount of the Notes Payable to GST as payment-in-kind (“PIK”) interest, with interest due on January 31 of each year. In conjunction with the interest payments in 2017 and 2016 , $19.3 million and $18.4 million , respectively, was paid in cash and PIK interest of $13.4 million and $12.7 million , respectively, was added to the principal balance of the Notes Payable to GST. With the reconsolidation of GST in the third quarter, these borrowings became intercompany and thus were no longer reported on our Consolidated Balance Sheet beginning in that quarter. In the fourth quarter, the notes were paid off internally. We regularly transacted business with GST through the purchase and sale of products while it was not consolidated in EnPro's financial statements. We also provided services for GST including information technology, supply chain, treasury, accounting and tax administration, legal, and human resources under a support services agreement. GST is included in our consolidated U.S. federal income tax return and certain state combined income tax returns. As the parent of these consolidated tax groups, we are liable for, and pay, income taxes owed by the entire group. We had agreed with GST to allocate group taxes to GST based on the U.S. consolidated tax return regulations and current income tax accounting guidance. This method generally allocates taxes to GST as if it were a separate taxpayer. As a result, at December 31, 2016 we carried an income tax receivable from GST related to this allocation. We did not carry a receivable at December 31, 2017 on our consolidated balance sheet as a result of the reconsolidation of GST. As discussed further in Note 2, "Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC," on January 30, 2017, OldCo filed a voluntary petition for reorganization under Chapter 11 of the United States Bankruptcy Code. We provided similar services to OldCo to those mentioned above for GST during the period from the OldCo Petition Date through the consummation of the Joint Plan, when it was reconsolidated into EnPro, but on a much less extensive basis due to OldCo's limited operations. Amounts included in our consolidated financial statements arising from transactions with GST and OldCo during the periods which they were not consolidated in our results include the following: Consolidated Statements of Operations Caption Seven Months Ended July 30, 2017 Years Ended December 31, Description 2016 2015 (in millions) Sales to GST Net sales $ 20.8 $ 28.0 $ 30.6 Purchases from GST Cost of sales $ 12.2 $ 17.7 $ 20.7 Interest expense to GST Interest expense $ 20.6 $ 33.5 $ 31.6 Consolidated Balance Sheets Caption December 31, 2016 Description (in millions) Due from GST Accounts receivable, net $ 21.4 Income tax receivable from GST Deferred income taxes and income tax receivable $ 119.0 Due from GST Other assets $ 1.4 Due to GST Accounts payable $ 6.3 Accrued interest to GST Accrued expenses $ 32.6

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Long-Term Debt	13. Long-Term Debt As of December 31, 2017 2016 (in millions) Senior Notes 444.2 294.1 Revolving debt 173.5 130.0 Other notes payable 0.8 0.9 618.5 425.0 Less current maturities of long-term debt 0.2 0.2 $ 618.3 $ 424.8 Senior Notes In September 2014, we issued $300.0 million aggregate principal amount of our Senior Notes. We issued the notes net of an original issue discount of $2.4 million . The Senior Notes are unsecured, unsubordinated obligations of EnPro and mature on September 15, 2022. Interest on the Senior Notes accrues at a rate of 5.875% per annum and is payable semi-annually in cash in arrears on March 15 and September 15 of each year. The debt discount is being amortized through interest expense until the maturity date resulting in an effective interest rate of 6.0% . The Senior Notes are required to be guaranteed on a senior unsecured basis by each of EnPro’s existing and future direct and indirect domestic subsidiaries that is a borrower under, or guarantees, our indebtedness under the Revolving Credit Facility or guarantees any other Capital Markets Indebtedness (as defined in the indenture governing the Senior Notes) of EnPro or any of the guarantors. We may, on any one or more occasions, redeem all or a part of the Senior Notes at specified redemption prices plus accrued and unpaid interest. In March 2017, we completed an add-on offering of $150.0 million of our 5.875% Senior Notes due 2022 (the “Additional Notes"). We issued the notes inclusive of an original issue premium of $1.5 million . The indenture for the Additional Notes contains the same interest payment, redemption, change of control, covenant, and guarantee provisions as for the Senior Notes. The debt premium is being amortized through interest expense until the maturity date resulting in an effective interest rate of 5.66% . The Additional Notes and the Senior Notes are treated as a single series of notes under the indenture governing these notes. The proceeds from the offering of the Additional Notes were used primarily to repay outstanding borrowings under the Revolving Credit Facility (described below) in order to increase availability to fund future capital requirements, including those funding requirements associated with the Joint Plan of OldCo and GST, which are described in Note 20, "Subsidiary Asbestos Bankruptcies." Each holder of the Senior Notes and Additional Notes may require us to repurchase some or all of the Senior Notes and Additional Notes for cash upon the occurrence of a defined “change of control” event. Our ability to redeem the Senior Notes and Additional Notes prior to maturity is subject to certain conditions, including in certain cases the payment of make-whole amounts. The indenture governing the Senior Notes and Additional Notes includes covenants that restrict our ability to engage in certain activities, including incurring additional indebtedness and paying dividends, subject in each case to specified exceptions and qualifications set forth in the indenture. Revolving Credit Facility On August 28, 2014, we amended and restated the agreement governing our senior secured revolving credit facility (the “Credit Facility Amendment”). The Credit Facility Amendment provides for a five year, $300.0 million senior secured revolving credit facility. At December 31, 2017, borrowings under the Revolving Credit Facility bore interest at an annual rate of LIBOR plus 2.00% or base rate plus 1.00% , although the interest rates under the Revolving Credit Facility are subject to incremental increases based on a consolidated total leverage ratio. In addition, a commitment fee accrues with respect to the unused amount of the Revolving Credit Facility. EnPro, EnPro Holdings, and Coltec are the permitted borrowers under the Revolving Credit Facility. Each of our domestic, consolidated subsidiaries are required to guarantee the obligations of the borrowers under the Revolving Credit Facility, and each of our existing domestic, consolidated subsidiaries has entered into the Credit Facility Amendment to provide such a guarantee. Borrowings under the Revolving Credit Facility are secured by a first priority pledge of certain of our assets. The Credit Facility Amendment contains financial covenants and required financial ratios, including a maximum consolidated total net leverage and a minimum consolidated interest coverage as defined in the agreement. The Credit Facility Amendment contains affirmative and negative covenants which are subject to customary exceptions and qualifications. We were in compliance with all covenants of the Credit Facility Amendment as of December 31, 2017 . In October 2016, the Revolving Credit Facility was amended to permit various transactions as part of the Coltec Restructuring. Permitted borrowers under the Revolving Credit Facility now include EnPro Holdings in addition to EnPro. The borrowing availability under our Revolving Credit Facility at December 31, 2017 was $111.5 million after giving consideration to $15.0 million of outstanding letters of credit and $ 173.5 million of outstanding borrowings. Scheduled Principal Payments Future principal payments on long-term debt are as follows: (in millions) 2018 $ 0.2 2019 173.7 2020 0.2 2021 0.1 2022 450.0 Thereafter 0.1 $ 624.3 The payments for long-term debt shown in the table above reflect the contractual principal amount for the Senior Notes. In the Consolidated Balance Sheets, these amounts are shown net of unamortized debt discounts aggregating $5.8 million pursuant to applicable accounting rules. Debt Issuance Costs During 2017, we capitalized $2.4 million of debt issuance costs in connection with the issuance of the Additional Notes. The capitalized debt issuance costs are amortized to interest expense over the life of the notes.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	14. Fair Value Measurements Assets and liabilities measured at fair value on a recurring basis are summarized as follows: Fair Value Measurements as of December 31, 2017 December 31, 2016 (in millions) Assets Time deposits $ — $ 26.0 Deferred compensation assets 7.8 7.0 $ 7.8 $ 33.0 Liabilities Deferred compensation liabilities $ 8.9 $ 8.3 Our time deposits and deferred compensation assets and liabilities are classified within Level 1 of the fair value hierarchy because they are valued using quoted market prices. The carrying values of our significant financial instruments reflected in the Consolidated Balance Sheets approximate their respective fair values, except for the following: December 31, 2017 December 31, 2016 Carrying Value Fair Value Carrying Value Fair Value (in millions) Long-term debt $ 618.5 $ 645.6 $ 425.0 $ 439.1 Notes payable to GST $ — $ — $ 295.9 $ 302.7 The fair values for long-term debt are based on quoted market prices, but this would be considered a Level 2 computation because the market is not active. The notes payable to GST computation would be considered Level 2 since it is based on rates available to us for debt with similar terms and maturities. Assets measured on a nonrecurring basis Long-lived Assets . We review the carrying amounts of long-lived assets when certain events or changes in circumstances indicate that the carrying amounts may not be recoverable. In consideration of the poor financial performance of the ATDynamics business, an asset group in the Stemco division of our Sealing Products segment, for the quarter ended September 30, 2017 and significantly lowered expectations for the fourth quarter forecast and the budget for fiscal year 2018, we determined that a test of ATDynamics' recoverability was required. An impairment loss is recognized when the carrying amount of the asset group is not recoverable and exceeds its fair value. We estimated the fair values of assets subject to long-lived asset impairment based on our own judgments about the assumptions that market participants would use in pricing the assets. In doing so, we used an income approach based upon discounted cash flows. The key assumptions used for the discounted cash flow approach include expected cash flows based on internal business plans, projected growth rates, discount rates, and royalty rates for certain intangible assets. We classified these fair value measurements as Level 3. As a result of this test, certain of ATDynamics' definite-lived intangible assets were determined to be impaired, and were valued in total at $1.7 million , resulting in an impairment loss of $10.1 million , which equaled the excess of these assets' net book value at September 30, 2017 over their fair value. The loss is reflected in other expense (operating) in the Consolidated Statement of Operations. Investment in GST and OldCo. As discussed further in Note 2, " Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC - Reconsolidation," the transaction to reconsolidate GST and OldCo into our reported financial results involved the measurement of the fair value of our investment in GST and OldCo as of July 31, 2017. The transaction was accounted for under the authoritative guidance for business combinations, and the investment's fair value of $485.2 million at this date was the deemed purchase price. The fair value was determined using a combination of a market approach based upon a multiple of GST and OldCo's trailing forecasted financial performance for fiscal 2017, and an income approach based upon discounted cash flows. The key assumptions used for the discounted cash flow approach include expected cash flows based on internal business plans, projected growth rates and discount rates. As a result, the valuation of the investment in GST is considered Level 3 due to the absence of quoted market prices or observable inputs.

Pensions and Postretirement Ben

Pensions and Postretirement Benefits	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
Pensions and Postretirement Benefits	15. Pensions and Post-retirement Benefits We have non-contributory defined benefit pension plans covering eligible employees in the United States, Mexico and several European countries. Salaried employees’ benefit payments are generally determined using a formula that is based on an employee’s compensation and length of service. We closed our defined benefit pension plan for new salaried employees in the United States who joined the Company after January 1, 2006, and, effective January 1, 2007, benefits were frozen for all salaried employees who were not age 40 or older as of December 31, 2006. Hourly employees’ benefit payments are generally determined using stated amounts for each year of service. Our employees also participate in voluntary contributory retirement savings plans for salaried and hourly employees maintained by us. Under these plans, eligible employees can receive matching contributions up to the first 6% of their eligible earnings. Effective January 1, 2007, those employees whose defined benefit pension plan benefits were frozen receive an additional 2% company contribution each year. Beginning on August 1, 2016, this additional contribution ceased being provided to future hires at the company, but was retained for those employees already receiving it. We recorded $11.5 million , $9.6 million and $9.2 million in expenses in 2017 , 2016 and 2015 , respectively, for matching contributions under these plans. Our general funding policy for qualified defined benefit pension plans historically has been to contribute amounts that are at least sufficient to satisfy regulatory funding standards. During 2017 and 2016 , we contributed $8.8 million and $14.8 million , respectively, in cash to our U.S. pension plans. The contributions were made in these years in order to meet a funding level sufficient to avoid variable fees from the PBGC on the underfunded portion of our pension liability. We made no contribution to our U.S. pension plans during 2015. We anticipate that we will make total contributions of $20 million in 2018 to our U.S. defined benefit pension plans. Additionally, we expect to make total contributions of approximately $0.8 million in 2018 to the foreign pension plans. The projected benefit obligation, accumulated benefit obligation and fair value of plan assets for the defined benefit pension plans with accumulated benefit obligations in excess of plan assets were $308.6 million , $302.6 million and $289.7 million at December 31, 2017 , and $286.7 million , $279.7 million and $254.3 million at December 31, 2016 , respectively. We provide, through non-qualified plans, supplemental pension benefits to a limited number of employees. Certain of our subsidiaries also sponsor unfunded postretirement plans that provide certain health-care and life insurance benefits to eligible employees. The health-care plans are contributory, with retiree contributions adjusted periodically, and contain other cost-sharing features, such as deductibles and coinsurance. The life insurance plans are generally noncontributory. The amounts included in “Other Benefits” in the following tables include the non-qualified plans and the other postretirement plans discussed above. The following table sets forth the changes in projected benefit obligations and plan assets of our defined benefit pension and other non-qualified and postretirement plans as of and for the years ended December 31, 2017 and 2016 . Pension Benefits Other Benefits 2017 2016 2017 2016 (in millions) Change in Projected Benefit Obligations Projected benefit obligations at beginning of year $ 289.7 $ 283.4 $ 3.2 $ 3.4 Service cost 4.5 4.3 0.1 0.1 Interest cost 12.9 12.7 0.1 0.2 Actuarial loss (gain) 16.1 8.9 — (0.3 ) Amendments 0.2 — — — Benefits paid (13.6 ) (18.1 ) (0.9 ) (0.2 ) Reconsolidation of GST and OldCo 58.8 — 2.1 — Other 0.6 (1.5 ) 0.1 — Projected benefit obligations at end of year 369.2 289.7 4.7 3.2 Change in Plan Assets Fair value of plan assets at beginning of year 256.9 242.5 Actual return on plan assets 42.3 17.3 Administrative expenses (0.8 ) (0.4 ) Benefits paid (13.6 ) (18.1 ) Company contributions 9.4 15.6 Reconsolidation of GST and OldCo 56.5 — Fair value of plan assets at end of year 350.7 256.9 Underfunded Status at End of Year $ (18.5 ) $ (32.8 ) $ (4.7 ) $ (3.2 ) Amounts Recognized in the Consolidated Balance Sheets Long-term assets $ 0.8 $ — $ — $ — Current liabilities (0.5 ) (0.4 ) (0.3 ) (0.1 ) Long-term liabilities (18.8 ) (32.4 ) (4.4 ) (3.1 ) $ (18.5 ) $ (32.8 ) $ (4.7 ) $ (3.2 ) Pre-tax charges recognized in accumulated other comprehensive loss as of December 31, 2017 and 2016 consist of: Pension Benefits Other Benefits 2017 2016 2017 2016 (in millions) Net actuarial (gain) loss $ 65.3 $ 78.4 $ (0.3 ) $ (0.4 ) Prior service cost 1.4 1.2 0.3 0.4 $ 66.7 $ 79.6 $ — $ — The accumulated benefit obligation for all defined benefit pension plans was $361.7 million and $281.6 million at December 31, 2017 and 2016 , respectively. The following table sets forth the components of net periodic benefit cost and other changes in plan assets and benefit obligations recognized in other comprehensive income for our defined benefit pension and other non-qualified and postretirement plans for the years ended December 31, 2017 , 2016 and 2015 . Pension Benefits Other Benefits 2017 2016 2015 2017 2016 2015 (in millions) Net Periodic Benefit Cost Service cost $ 4.5 $ 4.3 $ 4.9 $ 0.1 $ 0.1 $ 0.1 Interest cost 12.9 12.7 12.0 0.1 0.2 0.2 Expected return on plan assets (20.1 ) (17.2 ) (18.2 ) — — — Amortization of prior service cost 0.3 0.2 0.2 0.1 0.1 — Amortization of net loss 7.3 6.9 6.9 — — — Curtailment (0.1 ) (0.1 ) — — (0.3 ) — Deconsolidation of GST (0.3 ) (0.9 ) (0.7 ) — — — Net periodic benefit cost 4.5 5.9 5.1 0.3 0.1 0.3 Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income Net loss (gain) (5.8 ) 8.2 3.3 0.1 (0.4 ) (0.4 ) Prior service cost 0.5 — — — — 0.6 Amortization of net loss (7.3 ) (6.9 ) (6.9 ) — — — Amortization of prior service cost (0.3 ) (0.2 ) (0.2 ) (0.1 ) (0.1 ) — Other adjustment — — (0.1 ) — 0.3 — Total recognized in other comprehensive income (12.9 ) 1.1 (3.9 ) — (0.2 ) 0.2 Total Recognized in Net Periodic Benefit Cost and Other Comprehensive Income $ (8.4 ) $ 7.0 $ 1.2 $ 0.3 $ (0.1 ) $ 0.5 The estimated net loss and prior service cost for the defined benefit pension plans that will be amortized from accumulated other comprehensive loss into net periodic benefit cost over the next fiscal year are $5.4 million and $0.3 million , respectively. The estimated net loss for the other defined benefit postretirement plans that will be amortized from accumulated other comprehensive loss into net periodic benefit cost over the next fiscal year is insignificant. Pension Benefits Other Benefits 2017 2016 2015 2017 2016 2015 Weighted-Average Assumptions Used to Determine Benefit Obligations at December 31 Discount rate 3.75 % 4.25 % 4.63 % 3.75 % 4.25 % 4.63 % Rate of compensation increase 3.0 % 3.0 % 3.0 % 4.0 % 4.0 % 4.0 % Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost for Years Ended December 31 Discount rate 4.25 % 4.63 % 4.25 % 4.25 % 4.63 % 4.25 % Expected long-term return on plan assets 7.25 % 7.25 % 7.25 % — — — Rate of compensation increase 3.0 % 3.0 % 3.0 % 4.0 % 4.0 % 4.0 % The discount rate reflects the current rate at which the pension liabilities could be effectively settled at the end of the year. The discount rate was determined using a model, which uses a theoretical portfolio of high quality corporate bonds specifically selected to produce cash flows closely related to how we would settle our retirement obligations. This produced a discount rate of 3.75% at December 31, 2017 . As of the date of these financial statements, there are no known or anticipated changes in our discount rate assumption that will impact our pension expense in 2018 . A 25 basis point decrease (increase) in our discount rate, holding constant our expected long-term return on plan assets and other assumptions, would increase (decrease) pension expense by approximately $0.9 million per year. The overall expected long-term rate of return on assets was determined based upon weighted-average historical returns over an extended period of time for the asset classes in which the plans invest according to EnPro's current investment policy. We use the RP-2014 mortality table with the MP-2017 projection scale to value our domestic pension liabilities. Assumed Health Care Cost Trend Rates at December 31 2017 2016 Health care cost trend rate assumed for next year 8.0 % 8.0 % Rate to which the cost trend rate is assumed to decline (the ultimate rate) 4.5 % 4.5 % Year that the rate reaches the ultimate trend rate 2025 2024 A one percentage point change in the assumed health-care cost trend rate would have an insignificant impact on net periodic benefit cost and on benefit obligations. Plan Assets The asset allocation for pension plans at the end of 2017 and 2016 , and the target allocation for 2018 , by asset category are as follows: Target Allocation Plan Assets at December 31, 2018 2017 2016 Asset Category Equity securities 30 % 30 % 40 % Fixed income 70 % 70 % 60 % 100 % 100 % 100 % Our investment goal is to maximize the return on assets, over the long term, by investing in equities and fixed income investments while diversifying investments within each asset class to reduce the impact of losses in individual securities. Equity investments include a mix of U.S. large capitalization equities, U.S. small capitalization equities and non-U.S. equities. Fixed income investments include a mix of treasury obligations and high-quality money market instruments. The asset allocation policy is reviewed and any significant variation from the target asset allocation mix is rebalanced periodically. The plans have no direct investments in EnPro common stock. The plans invest exclusively in mutual funds whose holdings are marketable securities traded on recognized markets and, as a result, would be considered Level 1 assets. The investment portfolios of the various funds at December 31, 2017 and 2016 are summarized as follows: 2017 2016 (in millions) Mutual funds – U.S. equity $ 61.6 $ 65.7 Mutual funds - fixed income treasury and money market 244.6 153.3 Mutual funds – international equity 43.3 37.0 Cash equivalents 1.2 0.9 $ 350.7 $ 256.9 Estimated Future Benefit Payments The following benefit payments, which reflect expected future service, as appropriate, are expected to be paid: Pension Benefits Other Benefits (in millions) 2018 $ 16.4 $ 0.5 2019 17.1 0.5 2020 18.0 1.5 2021 18.8 0.5 2022 19.6 0.4 Years 2023 – 2027 111.2 1.5

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Stockholders' Equity	16. Shareholders' Equity In 2015, we adopted a policy under which we intend to declare regular quarterly cash dividends on our common stock, as determined by our board of directors, after taking into account our cash flows, earnings, financial position and other relevant matters. In accordance with this policy, total dividend payments of $19.0 million , $18.1 million , and $18.0 million were made during the years ended December 31, 2017 , 2016, and 2015, respectively. In February 2018, our Board of Directors declared a cash dividend of $0.24 per share payable on March 21, 2018 to shareholders of record at the close of business on March 8, 2018. In October 2017, our board of directors authorized a new program for the repurchase of up to $50.0 million of our outstanding common shares. This program authorization will expire in October 2020. In October 2015, our Board of Directors authorized the purchase of up to $50.0 million of our outstanding common shares from time to time, which expired in October 2017. During 2017, we repurchased 0.2 million shares for $11.5 million , all of which settled during the year. During 2016, we repurchased 0.6 million shares for $29.7 million under this authorization. The shares were retired upon purchase. Cash payments for purchases under this authorization that settled during 2016 were $30.4 million . During 2015, we repurchased 0.1 million additional shares for $6.0 million under the above authorization. Cash payments for purchases under this authorization that settled during 2015 were $5.3 million . In February 2015, our board of directors authorized the repurchase of up to $80.0 million of our outstanding common shares. The repurchase plan was completed in April 2015 after purchasing 1.2 million shares at an average price of $66.76 per share.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive (Loss)	17. Accumulated Other Comprehensive Loss Changes in accumulated other comprehensive loss by component (after tax) are as follows: (in millions) Unrealized Translation Adjustments Pension and Other Postretirement Plans Total Balance at December 31, 2014 $ 17.0 $ (51.1 ) $ (34.1 ) Other comprehensive loss before reclassifications (21.9 ) (1.8 ) (23.7 ) Amounts reclassified from accumulated other comprehensive income (loss) — 3.7 3.7 Net current-period other comprehensive loss (21.9 ) 1.9 (20.0 ) Balance at December 31, 2015 (4.9 ) (49.2 ) (54.1 ) Other comprehensive loss before reclassifications (16.1 ) (5.0 ) (21.1 ) Amounts reclassified from accumulated other comprehensive loss (0.2 ) 4.5 4.3 Net current-period other comprehensive loss (16.3 ) (0.5 ) (16.8 ) Balance at December 31, 2016 (21.2 ) (49.7 ) (70.9 ) Other comprehensive income before reclassifications 14.4 3.2 17.6 Amounts reclassified from accumulated other comprehensive loss — 4.9 4.9 Net current-period other comprehensive income 14.4 8.1 22.5 Balance at December 31, 2017 $ (6.8 ) $ (41.6 ) $ (48.4 ) Reclassifications out of accumulated other comprehensive loss are as follows: Details about Accumulated Other Comprehensive Loss Components Amount Reclassified from Accumulated Other Comprehensive Loss Affected Statement of Operations Caption Years Ended December 31, 2017 2016 2015 (in millions) Amortization of pension and other postretirement plans: Actuarial losses $ 7.3 $ 6.6 $ 6.9 (1) Prior service costs 0.4 0.3 0.2 (1) Total before tax 7.7 6.9 7.1 Tax benefit (2.8 ) (2.4 ) (3.4 ) Income tax expense Net of tax $ 4.9 $ 4.5 $ 3.7 Release of unrealized currency translation adjustment upon sale of investment in foreign entity, net of tax $ — $ (0.2 ) $ — Other non-operating expense (1) These accumulated other comprehensive income (loss) components are included in the computation of net periodic pension cost. (See Note 15, "Pensions and Postretirement Benefits" for additional details).

Equity Compensation Plan

Equity Compensation Plan	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Equity Compensation Plan	18. Equity Compensation Plan We have an equity compensation plan (the “Plan”) that provides for the delivery of up to 6.2 million shares pursuant to various market and performance-based incentive awards. As of December 31, 2017 , there are 0.7 million shares available for future awards. Our policy is to issue new shares to satisfy share delivery obligations for awards made under the Plan. The Plan allows awards of restricted share units to be granted to executives and other key employees. Generally, all share units will vest in three years. Compensation expense related to the restricted share units is based upon the market price of the underlying common stock as of the date of the grant and is amortized over the applicable restriction period using the straight-line method. As of December 31, 2017 , there was $5.2 million of unrecognized compensation cost related to restricted share units expected to be recognized over a weighted-average vesting period of 1.3 years. Under the terms of the Plan, performance share awards were granted to executives and other key employees during 2017 , 2016 and 2015 . Each grant will vest if EnPro achieves specific financial objectives at the end of each three-year performance period. Additional shares may be awarded if objectives are exceeded, but some or all shares may be forfeited if objectives are not met. Performance shares earned at the end of a performance period, if any, will be paid in actual shares of our common stock, less the number of shares equal in value to applicable withholding taxes if the employee chooses. During the performance period, a grantee receives dividend equivalents accrued (if any) in cash, and shares are forfeited if a grantee terminates employment. Compensation expense related to the performance shares granted is computed using the fair value of the awards at the date of grant. Potential shares to be issued for performance share awards granted in 2017 and 2016 are subject to a market condition based on the performance of our stock, measured based upon a calculation of total shareholder return, compared to a group of peer companies. The fair value of these awards was determined using a Monte Carlo simulation methodology. Compensation expense for these awards is computed based upon this grant date fair value using the straight-line method over the applicable performance period. The Monte Carlo simulation model utilizes multiple input variables that determine the probability of satisfying the market condition stipulated in the award and calculates the fair value of each award. We issued performance share awards to eligible participants on February 13, 2017 and February 23, 2016. We used the following assumptions in determining the fair value of these awards: Expected stock price volatility Annual expected dividend yield Risk free interest ate Correlation between Total Shareholder Return for EnPro and the applicable S&P index Shares granted February 13, 2017 EnPro Industries, Inc. 31.23 % 1.23 % 1.45 % 0.6259 S&P 600 Capital Goods Index 34.86 % n/a 1.45 % Shares granted February 23, 2016 EnPro Industries, Inc. 27.36 % 1.82 % 0.88 % 0.5895 S&P 600 Capital Goods Index 32.80 % n/a 0.88 % The risk free rate equals the yield, as of the Valuation Date, on zero-coupon U.S. Treasury STRIPS that have a remaining term equal to the length of the remaining performance cycle. The expected volatility assumption for us and each member of the peer group is based on each entity’s historical stock price volatility over a period equal to the length from the Valuation Date to the end of the performance cycle. The annual expected dividend yield is based on annual expected dividend payments and the stock price on the date of grant. Potential shares to be issued for performance share awards granted in 2015 are subject to our operating performance. Compensation expense related to the performance shares is computed using the market price of the underlying common stock as of the date of the grant and the currently forecasted achievement level of the specific financial objectives and is recorded using the straight-line method over the applicable performance period. As of December 31, 2017 , there was $3.0 million of unrecognized compensation cost related to nonvested performance share awards that is expected to be recognized over a weighted-average vesting period of 1.3 years. Restricted shares, with three or four-year restriction periods from the initial grant date were issued in 2013 and 2012 to executives and other key employees. Compensation expense related to the restricted shares was based upon the market price of the underlying common stock as of the date of the grant and was amortized over the applicable restriction period using the straight-line method. As of December 31, 2017 , there was no unrecognized compensation cost related to restricted shares. A summary of award activity under these plans is as follows: Restricted Share Units Performance Shares Restricted Stock Shares Weighted- Average Grant Date Fair Value Shares Weighted- Average Grant Date Fair Value Shares Weighted- Average Grant Date Fair Value Nonvested at December 31, 2014 269,585 $ 54.60 227,220 $ 55.65 11,330 $ 55.09 Granted 94,623 63.98 115,197 68.31 — — Vested (38,457 ) 37.67 (98,230 ) 44.63 — — Forfeited (34,157 ) 59.34 (3,398 ) 60.09 — — Achievement level adjustment — — (42,387 ) 44.63 — — Shares settled for cash (27,563 ) 37.65 — — — — Nonvested at December 31, 2015 264,031 61.74 198,402 67.22 11,330 55.09 Granted 111,320 44.29 199,965 49.68 — — Vested (59,104 ) 45.20 — — (11,330 ) 55.09 Forfeited (42,090 ) 58.48 (37,542 ) 54.66 — — Achievement level adjustment — — (77,310 ) 71.83 — — Shares settled for cash (12,135 ) 44.63 — — — — Nonvested at December 31, 2016 262,022 59.43 283,515 54.84 — — Granted 77,120 68.55 84,534 76.93 — — Vested (79,417 ) 64.16 (76,487 ) 63.81 — — Forfeited (17,607 ) 56.32 (8,823 ) 61.43 — — Achievement level adjustment — — (12,140 ) 63.81 — — Shares settled for cash (6,561 ) 54.29 — — — — Nonvested at December 31, 2017 235,557 $ 57.87 270,599 $ 61.92 — $ — The number of nonvested performance share awards shown in the table above represents the maximum potential shares to be issued. Non-qualified and incentive stock options were granted in 2011 and 2008. No stock option has a term exceeding 10 years from the date of grant. All stock options were granted at not less than 100% of fair market value (as defined) on the date of grant. As of December 31, 2017 , there was no unrecognized compensation cost related to stock options. A summary of option activity under the Plan as of December 31, 2017 , and changes during the year then ended, is presented below: Share Options Outstanding Weighted Average Exercise Price Balance at December 31, 2016 79,505 $ 36.31 Exercised (61,318 ) 34.55 Balance at December 31, 2017 18,187 $ 42.24 The outstanding options are all exercisable, with an exercise price of $42.24 and a remaining contractual life of 3.12 years. The year-end intrinsic value related to stock options is presented below: As of and for the Years Ended December 31, (in millions) 2017 2016 2015 Options outstanding $ 0.9 $ 2.5 $ 0.9 Options exercisable $ 0.9 $ 2.5 $ 0.9 Options exercised $ 2.2 $ 0.7 $ 0.1 We recognized the following equity-based employee compensation expenses and benefits related to our Plan activity: Years Ended December 31, (in millions) 2017 2016 2015 Compensation expense $ 9.5 $ 5.1 $ 4.1 Related income tax benefit $ 3.6 $ 1.9 $ 1.5 Each non-employee director received an annual grant of phantom shares equal in value to $95,000 in the year ended December 31, 2017 and $90,000 in the years ended December 31, 2016 and 2015. With respect to certain phantom shares awarded in prior years, we will pay each non-employee director in cash the fair market value of the director's phantom shares upon termination of service as a member of the board of directors. The remaining phantom shares granted will be paid out in the form of one share of our common stock for each phantom share, with the value of any fractional phantom shares paid in cash. Expense recognized in the years ended December 31, 2017 , 2016 and 2015 related to these phantom share grants was $0.7 million , $1.2 million and $0.7 million , respectively. Cash payments of $1.4 million were used to settle phantom shares in 2017 . No cash payments were used to settle phantom shares in 2016 or 2015 .

Business Segment Information

Business Segment Information	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Business Segment Information	19. Business Segment Information We aggregate our operating businesses into three reportable segments. The factors considered in determining our reportable segments are the economic similarity of the businesses, the nature of products sold or services provided, the production processes and the types of customers and distribution methods. Our reportable segments are managed separately based on these differences. Our Sealing Products segment designs, manufactures and sells sealing products, including: metallic, non-metallic and composite material gaskets, dynamic seals, compression packing, resilient metal seals, elastomeric seals, custom-engineered mechanical seals for applications in the aerospace industry and other markets, hydraulic components, expansion joints, flange sealing and isolation products, pipeline casing spacers/isolators, casing end seals, modular sealing systems for sealing pipeline penetrations, sanitary gaskets, hoses and fittings for the hygienic process industries, hole forming products, manhole infiltration sealing systems, bellows and bellows assemblies, pedestals for semiconductor manufacturing, PTFE products, and heavy-duty commercial vehicle parts used in the wheel-end, braking, suspension, and tire and mileage optimization systems. Our Engineered Products segment includes operations that design, manufacture and sell self-lubricating, non-rolling metal-polymer, solid polymer and filament wound bearing products, aluminum blocks for hydraulic applications, and precision engineered components and lubrication systems for reciprocating compressors. Our Power Systems segment designs, manufactures, sells and services heavy-duty, medium-speed diesel, natural gas and dual fuel reciprocating engines. Segment profit is total segment revenue reduced by operating expenses, restructuring and other costs identifiable with the segment. Corporate expenses include general corporate administrative costs. Expenses not directly attributable to the segments, corporate expenses, net interest expense, asset impairments, gains and losses related to the sale of assets, and income taxes are not included in the computation of segment profit. The accounting policies of the reportable segments are the same as those for EnPro. Segment operating results and other financial data for the years ended December 31, 2017 , 2016 , and 2015 were as follows: Years Ended December 31, 2017 2016 2015 (in millions) Sales Sealing Products $ 804.3 $ 705.6 $ 705.6 Engineered Products 301.1 277.1 297.8 Power Systems 208.2 208.3 204.6 1,313.6 1,191.0 1,208.0 Intersegment sales (4.0 ) (3.3 ) (3.6 ) Total sales $ 1,309.6 $ 1,187.7 $ 1,204.4 Segment Profit Sealing Products $ 90.9 $ 81.8 $ 84.3 Engineered Products 29.8 12.4 6.4 Power Systems 29.0 17.0 27.1 Total segment profit 149.7 111.2 117.8 Corporate expenses (34.3 ) (30.0 ) (28.2 ) Goodwill and other intangible asset impairment (10.1 ) — (47.0 ) Asbestos settlement — (80.0 ) — Interest expense, net (49.4 ) (55.1 ) (52.1 ) Gain on reconsolidation of GST and OldCo 534.4 — — Other expense, net (12.8 ) (14.8 ) (9.1 ) Income (loss) before income taxes $ 577.5 $ (68.7 ) $ (18.6 ) No customer accounted for 10% or more of net sales in 2017 , 2016 or 2015 . Years Ended December 31, 2017 2016 2015 (in millions) Capital Expenditures Sealing Products $ 20.4 $ 22.9 $ 17.0 Engineered Products 9.9 7.2 14.8 Power Systems 10.7 5.7 4.9 Corporate — — 0.1 Total capital expenditures $ 41.0 $ 35.8 $ 36.8 Depreciation and Amortization Expense Sealing Products $ 41.8 $ 35.1 $ 34.3 Engineered Products 16.8 17.5 19.4 Power Systems 5.2 4.4 4.1 Corporate — 0.1 0.3 Total depreciation and amortization $ 63.8 $ 57.1 $ 58.1 Net Sales by Geographic Area United States $ 750.6 $ 682.4 $ 696.2 Europe 292.6 289.9 289.5 Other foreign 266.4 215.4 218.7 Total $ 1,309.6 $ 1,187.7 $ 1,204.4 Net sales are attributed to countries based on location of the customer. As of December 31, 2017 2016 (in millions) Assets Sealing Products $ 1,078.0 $ 636.4 Engineered Products 229.2 210.0 Power Systems 210.8 164.8 Corporate 368.1 535.2 $ 1,886.1 $ 1,546.4 Long-Lived Assets United States $ 206.9 $ 148.6 France 26.5 23.0 Other Europe 23.4 20.7 Other foreign 40.1 23.1 Total $ 296.9 $ 215.4 Corporate assets include all of our cash and cash equivalents, investment in GST, and long-term deferred income taxes. Long-lived assets consist of property, plant and equipment.

Subsidiary Asbestos Bankruptcie

Subsidiary Asbestos Bankruptcies	12 Months Ended
	Dec. 31, 2017
Reorganization Items [Abstract]
Subsidiary Asbestos Bankruptcies	2. Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC On the GST Petition Date, GST LLC filed voluntary petitions for reorganization under Chapter 11 of the United States Bankruptcy Code (the "GST Chapter 11 Case") in the Bankruptcy Court. The filings were the initial step in a claims resolution process for an efficient and permanent resolution of all pending and future asbestos claims through court approval of a plan of reorganization to establish a facility to resolve and pay all GST asbestos claims. On March 17, 2016, we announced that we had reached a comprehensive consensual settlement to resolve current and future asbestos claims which contemplated the joint plan of reorganization (the "Joint Plan") which was filed with the Bankruptcy Court. This settlement contemplated that Coltec would, subject to the receipt of necessary consents, undergo a corporate restructuring (the “Coltec Restructuring”) in which all of its significant operating assets and subsidiaries, which included each of the Company’s major business units, would be distributed to a new direct subsidiary of the Company, which would also assume all of Coltec’s non-asbestos liabilities. The Coltec Restructuring was completed on December 31, 2016, and included the merger of Coltec with and into OldCo, LLC (“OldCo”), an indirect subsidiary of EnPro. As further contemplated by the settlement, on January 30, 2017 (the "OldCo Petition Date"), OldCo filed a Chapter 11 bankruptcy petition with the Bankruptcy Court (the "OldCo Chapter 11 Case"). On February 3, 2017, the Bankruptcy Court issued an order for the joint administration of the OldCo Chapter 11 Case with the GST Chapter 11 Case. The Joint Plan was consummated on July 31, 2017. For more detail on the terms of the Joint Plan, see Note 20, "Subsidiary Asbestos Bankruptcies." During the pendency of the GST Chapter 11 Case and the related OldCo Chapter 11 Case, which are described further in Note 20, "Subsidiary Asbestos Bankruptcies," certain actions proposed to be taken by GST or OldCo not in the ordinary course of business were subject to approval by the Bankruptcy Court. As a result, during the pendency of the GST Chapter 11 Case and the OldCo Chapter 11 Case, we did not have exclusive control over these companies. Accordingly, as required by GAAP, GST was deconsolidated beginning on the GST Petition Date and OldCo was deconsolidated beginning on the OldCo Petition Date. Reconsolidation GST and OldCo were reconsolidated upon the effective date of the consummation of the Joint Plan, which effective date was 12:01 a.m. on July 31, 2017. The reconsolidation of GST and OldCo was treated as a business acquisition in accordance with applicable accounting rules. The primary businesses comprising GST will be managed as part of the Garlock division within our Sealing Products segment. Smaller businesses also reconsolidated with GST will be managed by the Technetics and Stemco divisions within this segment, by the CPI division within our Engineered Products segment, and by the Fairbanks Morse division, which comprises our Power Systems segment. The following table presents the preliminary fair value of the net assets of GST and OldCo acquired. The initial estimates reported at September 30, 2017 have been modified at December 31, 2017 due to an increase in the valuation of other assets by $7.1 million . These estimates remain subject to the final completion of the valuation process for GST and OldCo: (in millions) Accounts receivable $ 22.9 Inventories 29.2 Property, plant and equipment 63.2 Goodwill 125.5 Other intangible assets 180.8 Other assets 174.1 Liabilities assumed (110.5 ) Total purchase price $ 485.2 In accordance with GAAP, the purchase price for the acquisition was equal to the fair value of our investment in GST and OldCo on the reconsolidation date. In the reconsolidation, the investment in GST and OldCo is deemed to be exchanged for our exclusive control of these businesses. No cash is transferred in the reconsolidation transaction, other than the reconsolidation of GST's and OldCo's cash and cash equivalents at that date. The purchase price was allocated to the assets and liabilities reconsolidated with these businesses based on their estimated fair values. The excess of the purchase price over the identifiable assets acquired less the liabilities assumed was reflected as goodwill. Goodwill recorded as part of the purchase price allocation was $125.5 million , none of which is expected to be tax deductible given the nature of the transaction. See Note 10, "Goodwill and Other Intangible Assets" for information on goodwill by reportable segment from this transaction. The goodwill recognized in this transaction is primarily attributable to intangible assets that do not qualify for separate recognition. Identifiable intangible assets acquired as part of the acquisition were $180.8 million , including $40.4 million of indefinite-lived trade names and $140.4 million of definite-lived intangible assets. Definite-lived intangible assets included customer relationships of $85.4 million , proprietary technology of $50.8 million , and a favorable supply agreement valued at $4.2 million . The definite-lived intangible assets have an initial weighted average amortization period of 15 years for each class. Post-reconsolidation sales of $81.3 million and income before taxes of $6.5 million attributable to GST and OldCo are included in our Consolidated Statement of Operations for the year ended December 31, 2017. The following unaudited supplemental pro forma condensed consolidated financial results of operations for the Company for the years ended December 31, 2017 and 2016, are presented as if the reconsolidation had been completed on January 1, 2016: Years Ended December 31, 2017 2016 Pro forma net sales $ 1,402.5 $ 1,337.7 Pro forma net income $ 53.7 $ 520.0 Pro forma earnings per share - basic $ 2.52 $ 24.07 Pro forma earnings per share - diluted $ 2.46 $ 23.85 The 2017 supplemental pro forma net income was adjusted to exclude $4.1 million of pre-tax nonrecurring expenses related to the fair value adjustment to acquisition date inventory. The 2016 supplemental pro forma net income was adjusted to include these charges. Pro forma net income for the year ended December 31, 2016 also includes the gain on reconsolidation discussed further below, as well as the tax impact of the reconsolidation discussed in Note 5, "Income Taxes." The supplemental pro forma net income for the years ended December 31, 2017 and 2016 was also adjusted to exclude a combined $(16.7) million and $148.2 million , respectively, of non-recurring expenses (credits) associated with the aforementioned asbestos claims resolution process recorded at EnPro and at GST and OldCo, as the process is assumed to have concluded in order for the reconsolidation to occur. The amount adjusted for the year ended December 31, 2017 is inclusive of $24.7 million of credits for insurance reimbursements that became realizable for GST and OldCo in the current year. The amount adjusted for the year ended December 31, 2016 is inclusive of charges of $80.0 million and $49.5 million recorded by EnPro and GST, respectively, in that year in association with the Joint Plan to resolve current and future asbestos claims and the agreement with the Canadian provincial workers' compensation boards (the "Provincial Boards") resolving remedies the Provincial Boards may possess against Garlock of Canada Ltd, GST, Coltec or any of their affiliates. See Note 20, "Subsidiary Asbestos Bankruptcies." The remaining amount adjusted for each year consists of charges for Chapter 11 case-related fees and expenses including attorneys' and experts' fees and fees associated with the administration of Garrison. These unaudited supplemental pro forma financial results have been prepared for comparative purposes only. The pro forma information does not purport to be indicative of the results of operations that actually would have resulted had the reconsolidation occurred on January 1, 2016, or of future results of the consolidated entities. Associated with the reconsolidation of GST and OldCo, we recorded a pretax gain of $534.4 million . The amounts comprising the gain include: (in millions) Gain on revaluation of investment in GST and OldCo $ 248.3 Elimination of net amounts payable to GST and OldCo at reconsolidation date 286.1 Total $ 534.4 The gain on revaluation of our investment in GST and OldCo is the difference between the above-noted fair value of the investment and its book value of $236.9 million as of the date of reconsolidation. Although EnPro's investment in OldCo was negative at the time that it was deconsolidated from the EnPro results, EnPro Holdings had entered into a keep well agreement with OldCo under which it unconditionally agreed to make equity contributions to OldCo sufficient to maintain OldCo's ability to pay and discharge its liabilities as they become due and payable. As a result of this agreement, we recorded a liability on our Consolidated Balance sheet that represented this obligation related to our investment in OldCo. The portion of the gain attributable to elimination of net amounts payable to GST and OldCo is based upon the balances in EnPro's amounts due to and from GST and OldCo as of that date, including the notes payable to GST and related accrued interest, income tax receivable from GST, and other payables to and receivables from GST that arose in the normal course of business. 20. Subsidiary Asbestos Bankruptcies The historical business operations of certain of our subsidiaries, principally Garlock Sealing Technologies LLC (“GST LLC”) and The Anchor Packing Company (“Anchor”), had resulted in a substantial volume of asbestos litigation in which plaintiffs alleged personal injury or death as a result of exposure to asbestos fibers. On June 5, 2010 (the “GST Petition Date”), GST LLC, Anchor and another subsidiary, Garrison Litigation Management Group, Ltd. (“Garrison”), filed voluntary petitions for reorganization under Chapter 11 of the United States Bankruptcy Code (the “GST Chapter 11 Case”) in the U.S. Bankruptcy Court for the Western District of North Carolina in Charlotte (the “Bankruptcy Court”). GST LLC, Anchor and Garrison are sometimes referred to collectively as “GST” in this report. These filings were the initial step in a claims resolution process for an efficient and permanent resolution of pending and future asbestos claims through court approval of a plan of reorganization to establish a facility to resolve and pay all GST asbestos claims. The filings on the GST Petition Date did not include EnPro Industries, Inc. or any other EnPro Industries, Inc. operating subsidiary. GST LLC is one of the businesses in our broader Garlock group and, prior to the GST Petition Date, was included in our Sealing Products segment. GST LLC and its subsidiaries operate five manufacturing facilities, including operations in Palmyra, New York and Houston, Texas. The financial results of GST and subsidiaries were included in our consolidated results through June 4, 2010, the day prior to the GST Petition Date. However, U.S. generally accepted accounting principles (“GAAP”) require an entity that files for protection under the U.S. Bankruptcy Code, whether solvent or insolvent, whose financial statements were previously consolidated with those of its parent, as GST’s and its subsidiaries’ were with ours, generally must be prospectively deconsolidated from the parent and the investment accounted for using the cost method. At deconsolidation, our investment was recorded at its estimated fair value as of June 4, 2010, resulting in a gain for reporting purposes. The cost method required us to present our ownership interests in the net assets of GST at the GST Petition Date as an investment and we did not recognize any income or loss from GST and subsidiaries in our results of operations until the reconsolidation of these subsidiaries upon consummation of a plan of reorganization under these proceedings. In January 2015, we announced that GST and we had reached an agreement with the court-appointed representative of future asbestos claimants (the “GST FCR”) in the GST Chapter 11 Case that included a second amended plan of reorganization. The second amended plan was filed with the Bankruptcy Court on January 14, 2015 and superseded the prior reorganization plans filed by GST in the GST Chapter 11 Case. The GST FCR agreed to support, recommend and vote in favor of the second amended plan. The second amended plan would have provided for the establishment of two facilities - a settlement facility (which would receive $220 million from GST and $30 million from our then-consolidated Coltec Industries Inc subsidiary (“Coltec”) upon consummation of the second amended plan and additional contributions from GST aggregating $77.5 million over the seven years) and a litigation fund (which would receive $30 million from GST) to fund the defense and payment of claims of claimants who elect to pursue litigation under the second amended plan rather than accept the settlement option under the second amended plan. Funds contained in the settlement facility and the litigation fund would have provided the exclusive remedies for current and future GST asbestos claimants other than claimants whose claims had been resolved by settlement or verdict prior to the GST Petition Date and were not paid prior to the GST Petition Date. Under the terms of the second amended plan, we would have retained 100% of the equity interests of GST LLC. The second amended plan would have provided for the extinguishment of any derivative claims against us based on GST asbestos products and operations, but would not have protected us or our other subsidiaries, including Coltec, from non-derivative asbestos claims. In light of the filing of the second amended proposed plan of reorganization by GST on January 14, 2015, GST undertook to revise its estimate of ultimate costs to resolve all asbestos claims against it. Under the second amended plan, not less than $367.5 million would be required to fund the resolution of all GST asbestos claims, $30 million of which would be funded by Coltec. As a result, GST believed the low end of the range of values that would be necessary for it to resolve all present and future claims to be $337.5 million . Accordingly, GST revised its estimate of its ultimate asbestos expenditures to $337.5 million and had accrued its liability at December 31, 2015 at that amount and Coltec had accrued a liability of $30 million at December 31, 2015, which accrual was reflected in our consolidated financial results for 2015, in connection with its contribution to be made pursuant to the second amended plan. While the GST FCR had agreed to support the second amended plan of reorganization, the official committee representing current asbestos claimants (the “GST Committee”) in the GST Chapter 11 Case and their law firms opposed the second amended plan of reorganization. Accordingly, GST continued to seek a consensual resolution that would also be acceptable to representatives of current asbestos claimants as well as the GST FCR. On March 17, 2016, EnPro announced that it had reached a comprehensive settlement (the “Consensual Settlement”) to resolve current and future asbestos claims. The settlement was reached with the GST Committee and the GST FCR, and representatives for current and future asbestos claimants (the “Coltec Representatives”) against Coltec also joined in the settlement. Under the settlement, the GST Committee, the GST FCR and the Coltec Representatives agreed to join GST and Coltec in proposing a joint plan of reorganization (the “Joint Plan”) and to ask asbestos claimants and the court to approve the Joint Plan. The Joint Plan was filed with the Bankruptcy Court on May 20, 2016 and amendments to the Joint Plan were filed with the Bankruptcy Court on June 21, 2016, July 29, 2016, December 2, 2016, April 3, 2017, May 14, 2017, May 19, 2017, June 8, 2017, and June 9, 2017. As so modified, the Joint Plan superseded all prior plans of reorganization filed by GST with the Bankruptcy Court. Following receipt of all necessary asbestos claimant and judicial approvals, including approval by the United States District Court for the Western District of North Carolina (the “District Court”), the Joint Plan was consummated and became effective at 12:01 a.m. on July 31, 2017 (the “Joint Plan Effective Date”). The Joint Plan and Consensual Settlement contemplated that, as an appropriate and necessary step to facilitate the implementation of the Consensual Settlement and not to delay or hinder creditors or the resolution of claims, Coltec would, subject to the receipt of necessary consents, undergo a corporate restructuring (the “Coltec Restructuring”) in which all of its significant operating assets and subsidiaries, which included each of our major business units, would be distributed to a new direct EnPro subsidiary, EnPro Holdings, Inc. (“EnPro Holdings”). EnPro Holdings would also assume all of Coltec’s non-asbestos liabilities. The Coltec Restructuring was completed on December 31, 2016, and included the merger of Coltec with and into OldCo, LLC (“OldCo”), which was a direct subsidiary of EnPro Holdings. OldCo, as the restructured entity, retained responsibility for all asbestos claims and rights to certain insurance assets of Coltec, as well as the business operated by our EnPro Learning System, LLC subsidiary (“EnPro Learning System”), which provides occupational safety training and consulting services to third parties. EnPro Learning System was also merged into OldCo. As contemplated by the Joint Plan, on January 30, 2017 (the “OldCo Petition Date”), OldCo, as the successor by merger to Coltec, filed a Chapter 11 bankruptcy petition with the Bankruptcy Court (the “OldCo Chapter 11 Case”). On February 3, 2017, the Bankruptcy Court issued an order for the joint administration of the OldCo Chapter 11 Case with the GST Chapter 11 Case. As required by GAAP, OldCo was deconsolidated beginning on the OldCo Petition Date. Accordingly the financial results of OldCo and its subsidiaries were included in our consolidated results through January 29, 2017, the day prior to the OldCo Petition Date. Pursuant to the Joint Plan, a claims resolution trust (the “Trust”) was established prior to the Joint Plan Effective Date. As contemplated by the Joint Plan, the Trust was funded (i) with aggregate cash contributions by GST LLC and Garrison of $350 million made immediately prior to the Joint Plan Effective Date, (ii) by the contribution made by OldCo immediately prior to the Joint Plan Effective Date of $50 million in cash and an option (the “Option”), exercisable one year after the Joint Plan Effective Date, permitting the Trust to purchase for $1 shares of EnPro common stock having a value of $20 million (with OldCo having the right to call the Option for payment of $20 million in cash at any time prior to the first anniversary of the Joint Plan Effective Date, with the Trust having the right to put the Option to OldCo for payment by OldCo of $20 million on the day prior to the first anniversary of the Joint Plan Effective Date and with the Option terminating on the second anniversary of the Joint Plan Effective Date in return for payment to the Trust of $20 million ), and (iii) by the obligations under the Joint Plan of OldCo to make a deferred contribution of $60 million in cash and of GST LLC and Garrison to make an aggregate deferred contribution of $20 million in cash no later than one year after the Joint Plan Effective Date. These deferred contributions were guaranteed by EnPro and secured by a pledge of 50.1% of the outstanding voting equity interests of GST LLC and Garrison. The Consensual Settlement included as a condition to our obligations to proceed with the settlement that EnPro, Coltec, GST and Garlock of Canada Ltd (an indirect subsidiary of GST LLC) enter into a written agreement, to be consummated concurrently with the consummation of the Joint Plan on the Joint Plan Effective Date, with the Canadian provincial workers’ compensation boards (the “Provincial Boards”) resolving remedies the Provincial Boards may possess against Garlock of Canada Ltd, GST, Coltec or any of their affiliates, including releases and covenants not to sue, for any present or future asbestos-related claim, and that the agreement is either approved by the Bankruptcy Court following notice to interested parties or the Bankruptcy Court concludes that its approval is not required. On November 11, 2016, we entered into such an agreement (the “Canadian Settlement”) with the Provincial Boards to resolve current and future claims against EnPro, GST, Garrison, Coltec, and Garlock of Canada Ltd for recovery of a portion of amounts the Provincial Boards have paid and will pay in the future under asbestos-injury recovery statutes in Canada for claims relating to asbestos-containing products. The Canadian Settlement provides for an aggregate cash settlement payment to the Provincial Boards of $20 million (U.S.), payable on the fourth anniversary of the effective date of the Joint Plan. Under the Canadian Settlement, after the effective date of the Joint Plan, the Provincial Boards had the option of accelerating the payment, in which case the amount payable would be discounted from the fourth anniversary of the effective date of the Joint Plan to the payment date at a discount rate of 4.5% per annum. In return, the Provincial Boards have separately agreed to provide a covenant not to sue EnPro, any of EnPro’s affiliates or the Trust for any present or future asbestos-related claims. On February 3, 2017, the Bankruptcy Court issued an order approving the Canadian Settlement. Prior to the Joint Plan Effective Date, the Provincial Boards provided notice of their election to accelerate the payment. After application of the discount resulting from such acceleration of payment, the settlement payment of approximately $16.7 million (U.S.) was made to the Provincial Boards on August 11, 2017. In light of the Consensual Settlement and the Canadian Settlement, in 2016 GST further revised its estimate of the ultimate costs to resolve all asbestos claims against it. Under the Joint Plan proposed pursuant to the Consensual Settlement, $480 million was required to fund the resolution of all asbestos claims against GST and OldCo, as the successor by merger to Coltec, $370.0 million of which funded by GST LLC and Garrison and $110.0 million of which funded by OldCo. In addition, GST estimated the amount necessary to resolve all current and future Canadian asbestos claims alleging disease, resulting in whole or in part from exposure to GST asbestos-containing products, to be $17.0 million , the net present value of the amount to be paid pursuant to the Canadian Settlement. GST revised its estimate of its ultimate asbestos expenditures to $387.0 million and had accrued its liability at December 31, 2016 at that amount. In addition, OldCo (then still a consolidated subsidiary) had accrued a liability of $110.0 million at December 31, 2016 in connection with its contributions to be made pursuant to the Joint Plan, with the accrual of the $80.0 million increase in its estimated liability being reflected in our consolidated financial results for 2016. On November 29, 2017, GST LLC, EnPro Holdings and EnPro entered into an agreement with the Trust to provide for the early settlement of the deferred contributions to the Trust under the Joint Plan and for the call of the Option by EnPro Holdings, as the successor by merger to OldCo. Under that agreement, in full satisfaction of the $60 million of aggregate deferred contribution obligations under the Joint Plan and payment of the $20 million call payment under the Option, on December 1, 2017 GST LLC, EnPro Holdings and EnPro paid $78.8 million (the “Early Cash Settlement Amount”) to the Trust and agreed to make a further payment to the Trust to the extent that total interest earned through July 31, 2018, with respect to a fixed income account in which the Early Cash Settlement Amount was invested by the Trust is less than $1.2 million . The Joint Plan permanently resolves current and future asbestos claims against GST LLC, Garrison and OldCo, as the successor by merger to Coltec, and injunctions issued under the Joint Plan protect all of EnPro and its subsidiaries from those claims, which claims are enjoined under Section 524(g) of the U.S. Bankruptcy Code. Under the Joint Plan, the Trust has assumed responsibility for all present and future asbestos claims arising from the operations or products of GST LLC, Garrison or Coltec/OldCo. Under the Joint Plan, EnPro, through its subsidiaries, retained ownership of OldCo, GST LLC and Garrison. Anchor, which has not conducted business operations for many years and had nominal assets, has been dissolved.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	21. Commitments and Contingencies General A description of environmental, asbestos and other legal matters relating to certain of our subsidiaries is included in this section. In addition to the matters noted herein, we are from time to time subject to, and are presently involved in, other litigation and legal proceedings arising in the ordinary course of business. We believe the outcome of such other litigation and legal proceedings will not have a material adverse effect on our financial condition, results of operations and cash flows. Expenses for administrative and legal proceedings are recorded when incurred. Environmental Our facilities and operations are subject to federal, state and local environmental and occupational health and safety requirements of the U.S. and foreign countries. We take a proactive approach in our efforts to comply with environmental, health and safety laws as they relate to our manufacturing operations and in proposing and implementing any remedial plans that may be necessary. We also regularly conduct comprehensive environmental, health and safety audits at our facilities to maintain compliance and improve operational efficiency. Although we believe past operations were in substantial compliance with the then applicable regulations, we or one or more of our subsidiaries are involved with various remediation activities at 15 sites where the future cost per site for us or our subsidiary is expected to exceed $0.1 million . Investigations have been completed for 11 sites and are in progress at the other 4 sites. Our costs at a majority of these sites relate to remediation projects for soil and groundwater contamination at former operating facilities that were sold or closed. Our policy is to accrue environmental investigation and remediation costs when it is probable that a liability has been incurred and the amount can be reasonably estimated. The measurement of the liability is based on an evaluation of currently available facts with respect to each individual situation and takes into consideration factors such as existing technology, presently enacted laws and regulations and prior experience in remediation of contaminated sites. Liabilities are established for all sites based on these factors. As assessments and remediation progress at individual sites, these liabilities are reviewed periodically and adjusted to reflect additional technical data and legal information. As of December 31, 2017 and 2016 , we had accrued liabilities of $ 27.3 million and $ 23.1 million , respectively, for estimated future expenditures relating to environmental contingencies. In 2017, in addition to the accruals described below, we accrued $1.1 million in liabilities to reflect our estimated share of certain EPA oversight costs at one site, estimated costs to expand the remediation system at one site, estimated costs to construct the remedial system at one site and our most current estimate of costs for continued remediation at five sites based upon a reassessment of the expected duration of remedial activities at each of those sites. These amounts have been recorded on an undiscounted basis in the Consolidated Balance Sheets. Given the uncertainties regarding the status of laws, regulations, enforcement policies, the impact of other parties potentially being liable, technology and information related to individual sites, we do not believe it is possible to develop an estimate of the range of reasonably possible environmental loss in excess of our recorded liabilities. Except as described below, we believe that our accruals for specific environmental liabilities are adequate for those liabilities based on currently available information. Actual costs to be incurred in future periods may vary from estimates because of the inherent uncertainties in evaluating environmental exposures due to unknown and changing conditions, changing government regulations and legal standards regarding liability. Based on our prior ownership of Crucible Steel Corporation a/k/a Crucible, Inc. (“Crucible”), we may have additional contingent liabilities in one or more significant environmental matters. One such matter, which is included in the 15 sites referred to above, is the Lower Passaic River Study Area of the Diamond Alkali Superfund Site in New Jersey. Crucible operated a steel mill abutting the Passaic River in Harrison, New Jersey from the 1930s until 1974, which was one of many industrial operations on the river dating back to the 1800s. Certain contingent environmental liabilities related to this site were retained by Coltec when Coltec sold a majority interest in Crucible Materials Corporation (the successor of Crucible) in 1985, which liabilities and other legacy non-asbestos liabilities were assumed by our subsidiary, EnPro Holdings, as part of the Coltec Restructuring The United States Environmental Protection Agency (the “EPA”) notified Coltec in September 2003 that it is a potentially responsible party (“PRP”) for Superfund response actions in the lower 17 -mile stretch of the Passaic River known as the Lower Passaic River Study Area. Coltec and approximately 70 of the numerous other PRPs, known as the Cooperating Parties Group, are parties to a May 2007 Administrative Order on Consent with the EPA to perform a Remedial Investigation/Feasibility Study (“RI/FS”) of the contaminants in the Lower Passaic River Study Area. The RI/FS was completed and submitted to the EPA at the end of April 2015. The RI/FS recommends a targeted dredge and cap remedy with monitored natural recovery and adaptive management for the Lower Passaic River Study Area. The cost of such remedy is estimated to be $726 million . Previously, on April 11, 2014, the EPA released its Focused Feasibility Study (the “FFS”) with its proposed plan for remediating the lower eight miles of the Lower Passaic River Study Area. The FFS calls for bank-to-bank dredging and capping of the riverbed of that portion of the river and estimates a range of the present value of aggregate remediation costs of approximately $ 953 million to approximately $ 1.73 billion , although estimates of the costs and the timing of costs are inherently imprecise. On March 3, 2016, the EPA issued the final Record of Decision (ROD) as to the remedy for the lower eight miles of the Lower Passaic River Study Area, with the maximum estimated cost being reduced by the EPA from $1.73 billion to $1.38 billion , primarily due to a reduction in the amount of cubic yards of material that will be dredged. In October 2016, Occidental Chemical Corporation, the successor to the entity that operated the Diamond Alkali chemical manufacturing facility, reached an agreement with the EPA to develop the design for this proposed remedy at an estimated cost of $165 million . The EPA has estimated that it will take approximately four years to develop this design. No final allocations of responsibility have been made among the numerous PRPs that have received notices from the EPA, there are numerous identified PRPs that have not yet received PRP notices from the EPA, and there are likely many PRPs that have not yet been identified. Based on our evaluation of the site, during 2014 we accrued a liability of $3.5 million related to environmental remediation costs associated with the lower eight miles of the Lower Passaic River Study Area, which is our estimate of the low end of a range of reasonably possible costs, with no estimate within the range being a better estimate than the minimum. Our actual remediation costs could be significantly greater than the $3.5 million we accrued. With respect to the upper nine miles of the Lower Passaic River Study Area, we are unable to estimate a range of reasonably possible costs. Another such matter involves the Onondaga Lake Superfund Site (the “Onondaga Site”) located near Syracuse, New York. Crucible operated a steel mill facility adjacent to Onondaga Lake from 1911 to 1983. The New York State Department of Environmental Conservation (“NYSDEC”) has contacted us and Coltec, as well as other parties, demanding reimbursement of unquantified environmental response costs incurred by NYSDEC and the EPA at the Onondaga Site. NYSDEC and EPA have alleged that contamination from the Crucible facility contributed to the need for environmental response actions at the Onondaga Site. In addition, Honeywell International Inc. (“Honeywell”), which has undertaken certain remediation activities at the Onondaga Site under the supervision of NYSDEC and the EPA, has informed us that it has claims against Coltec related to investigation and remediation at the Onondaga Site. We have entered into tolling agreements with NYSDEC, the EPA and Honeywell. On May 4, 2016, we received from Honeywell a summary of its claims. We have corresponded with Honeywell and have begun discussions with them regarding their claims. In addition, we have received notice from the Natural Resource Trustees for the Onondaga Lake Superfund Site (which are the U. S. Department of Interior, NYSDEC, and the Onondaga Nation) alleging that Coltec is considered to be a potentially responsible party for natural resource damages at the Onondaga Site. At this time, based on limited information we have with respect to estimated remediation costs and the respective allocation of responsibility for remediation among potentially responsible parties, we cannot estimate a reasonably possible range of loss associated with Crucible’s activities that may have affected the Onondaga Site. During 2016, we reserved $1.5 million for reimbursement of EPA response costs and certain costs associated with the remedial investigation. Except with respect to specific Crucible environmental matters for which we have accrued a portion of the liability set forth above, including the Lower Passaic River Study Area, we are unable to estimate a reasonably possible range of loss related to any other contingent environmental liability based on our prior ownership of Crucible. See the section entitled “Crucible Steel Corporation a/k/a Crucible, Inc.” in this footnote for additional information. In addition to the Crucible environmental matters discussed above, Coltec has received a notice from the EPA asserting that Coltec is a potentially responsible party under the Comprehensive Environmental Response, Compensation, and Liability Act ("CERCLA") as the successor to a former operator in 1954 and 1955 of two uranium mines in Arizona. On October 15, 2015, Coltec received another notice from the EPA asserting that Coltec is a potentially responsible party as the successor to the former operator of six additional uranium mines in Arizona. In 2015, we reserved $1.1 million for the minimum amount of probable loss associated with the first two mines identified by the EPA, including the cost of the investigative work to be conducted at such mines. During the second quarter of 2016, we reserved an additional $1.1 million for the minimum amount of probable loss associated with the six additional mines, which includes estimated costs of investigative work to be conducted at the eight mines. At September 30, 2017, we increased the reserve by $1.9 million to a balance of $4.0 million in anticipation of entering into an agreement with the EPA to perform investigations to determine the nature and extent of contamination at each site with the investigations to be completed by the end of 2019. On November 7, 2017, EnPro Holdings entered into an Administrative Settlement Agreement and Order on Consent for Interim Removal Action with EPA for the performance of this work. We cannot at this time estimate a reasonably possible range of loss associated with remediation or other incremental costs related to these mines. In connection with the former operation of a division of Colt Industries Inc, located in Water Valley, Mississippi, which Coltec divested to BorgWarner, Inc. ("BorgWarner") in 1996, Coltec has been managing trichloroethylene soil and groundwater contamination at the site. In February 2016, the Mississippi Department of Environmental Quality (MDEQ) issued an order against EnPro requiring evaluation of potential vapor intrusion into residential properties and commercial facilities located over the groundwater plume as well as requiring additional groundwater investigation and remediation. MDEQ performed the initial vapor intrusion investigations at certain residential and commercial sites, with the findings all being below the applicable screening level. In April 2016, the parties entered into a new order including negotiated time frames for groundwater remediation. Pursuant to that order, MDEQ performed a second round of seasonal vapor intrusion sampling beginning in August 2016. Results from sampling outside of three residences were above screening levels. Follow-up sampling directly underneath those residences (either sub-slab or in crawl spaces) were all below applicable screening levels. Two separate sampling events at another residence were also below applicable screening levels. Due to an increasing trend in vapor concentrations, MDEQ requested that we develop and implement initial corrective action measures to address vapor intrusion resulting from groundwater contamination in this residential area. These measures were developed and approved by MDEQ but could not be implemented because the owner of the private property where the corrective action system would be located would not provide access. An alternate plan has been submitted to and is being reviewed by MDEQ. In addition, vapor intrusion sampling at the manufacturing facility owned by BorgWarner was conducted during the first quarter of 2017. The results showed exceedances of screening levels at various areas in the plant and exceedances of levels requiring responsive actions in a limited area of the plant. Implementation of the immediate responsive actions has been completed and corrective action consisting of a permanent vapor intrusion remediation system became operational in May 2017. We are also continuing soil and groundwater investigation work in the area inside the plant where the vapor intrusion remediation system is located and around the outside of the plant and developing corrective action plans for both the contamination remaining at the plant as well as contamination that has migrated off-site. All of the work to be performed at the residential area, the plant and off-site is set forth in an agreed Order that we and MDEQ entered into on September 11, 2017. During the quarter ended March 31, 2016, we established an additional $1.3 million reserve with respect to this matter. During the year ended December 31, 2017 we reserved an additional $5.7 million for further investigation, additional remediation, long-term monitoring costs, and legal fees to support regulatory compliance for the above noted actions. During the quarter ended December 31, 2017, we reserved an additional $3.5 million for further investigation, additional remediation, long-term monitoring costs, and legal fees to support regulatory compliance for the above noted actions. The remaining reserve at December 31, 2017 is $3.8 million . As the corrective actions are implemented and their performance monitored, further modifications to the remediation system at the site may be required which may result in additional costs beyond the current reserve. On April 7, 2017, the State of Mississippi through its Attorney General filed suit against EnPro, OldCo and Goodrich Corporation in Mississippi Circuit Court in Yalobusha County seeking recovery of all costs and expenses to be incurred by the State in remediating the groundwater contamination, punitive damages and attorney’s fees. We plan to aggressively defend this case. The additional reserve established in the quarter ended December 31, 2017, noted above, does not include any estimate of contingent loss associated with this lawsuit other than due to remediation and other actions with respect to this site based on the MDEQ orders described above. In addition, it is our understanding that area homeowners, owners of commercial facilities and the local county government and possibly other private parties and individuals have engaged or may engage legal counsel to separately evaluate possible legal action relating to potential vapor intrusion and groundwater contamination. We have been further advised that certain of these parties intend to file legal action based on these claims. Based upon limited information regarding any further remediation or other actions that may be required at the site, we cannot estimate a minimum loss estimate or a reasonably possible range of loss for remediation costs. Crucible Steel Corporation a/k/a Crucible, Inc. Crucible, which was engaged primarily in the manufacture and distribution of high technology specialty metal products, was a wholly owned subsidiary of Coltec until 1983 when its assets and liabilities were distributed to a new Coltec subsidiary, Crucible Materials Corporation. Coltec sold a majority of the outstanding shares of Crucible Materials Corporation in 1985 and divested its remaining minority interest in 2004. Crucible Materials Corporation filed for Chapter 11 bankruptcy protection in May 2009 and is no longer conducting operations. We have certain ongoing obligations, which are included in other liabilities in our Consolidated Balance Sheets, including workers’ compensation, retiree medical and other retiree benefit matters, in addition to those mentioned previously related to Coltec’s period of ownership of Crucible. Based on Coltec’s prior ownership of Crucible, we may have certain additional contingent liabilities, including liabilities in one or more significant environmental matters included in the matters discussed in “Environmental” above. We are investigating these matters. Except with respect to those matters for which we have an accrued liability as discussed in "Environmental" above, we are unable to estimate a reasonably possible range of loss related to these contingent liabilities. Warranties We provide warranties on many of our products. The specific terms and conditions of these warranties vary depending on the product and the market in which the product is sold. We record a liability based upon estimates of the costs we may incur under our warranties after a review of historical warranty experience and information about specific warranty claims. Adjustments are made to the liability as claims data and historical experience necessitate. Changes in the carrying amount of the product warranty liability for the years ended December 31, 2017 , 2016 and 2015 are as follows: 2017 2016 2015 (in millions) Balance at beginning of year $ 5.0 $ 4.8 $ 3.5 Charges to expense 2.6 4.4 3.3 Settlements made (2.3 ) (4.2 ) (2.0 ) Balance at end of year $ 5.3 $ 5.0 $ 4.8 BorgWarner A subsidiary of BorgWarner has asserted claims against our subsidiary, GGB France E.U.R.L. (“GGB France”), regarding certain bearings supplied by GGB France to BorgWarner and used by BorgWarner in manufacturing hydraulic control units included in motor vehicle automatic transmission units, mainly that the bearings caused performance problems with and/or damage to the transmission units, leading to associated repairs and replacements. BorgWarner and GGB France participated in a technical review before a panel of experts to determine, among other things, whether there were any defects in such bearings that were a cause of the damages claimed by BorgWarner, including whether GGB France was required to notify BorgWarner of a change in the source of a raw material used in the manufacture of such bearings. This technical review was a required predicate to the commencement of a legal proceeding for damages. The expert panel issued a final report on technical and financial matters on April 6, 2017. In the final report, the expert panel concluded that GGB France had a duty to notify BorgWarner regarding the change of source of raw material used in the bearings, but that the failure of the hydraulic control units was attributable to both the raw material supplier change and the insufficient design of the units by BorgWarner. The expert panel provided detail on a possible allocation of damages alleged to have been incurred by BorgWarner and its customer. Although the language of the report is not clear, the report appears to note a potential allocation of recoverable damages 35% to BorgWarner and 65% to GGB France. It also indicates that, though it is for a court to ultimately determine, the aggregate damages to BorgWarner and its customer was in the range of 7.9 million EUR to 10.2 million EUR, with 1.8 million EUR to 2.1 million EUR of this range being for damages to BorgWarner and the remainder being for damages to its customer. The experts noted the lower end of the range as being more likely and noted a lack of sufficient evidence provided substantiating the customer's damages. Applying a 65% liability allocation to GGB to the total aggregate range yields a range of 5.1 million EUR to 6.6 million EUR. In the final report, the expert panel deferred to a court the determination of whether GGB France had breached its contractual obligations to BorgWarner. On October 25, 2017, BorgWarner initiated a legal proceeding against GGB with respect to this matter by filing a writ of claim with the Commercial Court of Brive, France. The parties have begun briefing their legal positions and we expect court hearings to begin in the summer of 2018. We continue to believe that GGB France has valid factual and legal defenses to these claims and we are vigorously defending these claims. Among GGB France’s legal defenses are a contractual disclaimer of consequential damages, which, if controlling, would limit liability for consequential damages and provide for the replacement of the bearings at issue, at an aggregate replacement value we estimate to be approximately 0.4 million EUR; that the determination of any duty to notify of the change in the source of the raw material is a legal matter to be determined by the presiding court; and the insufficiency of evidence of damage to BorgWarner's customer provided to the expert panel. Based on the final report from the expert panel and GGB France's legal defenses described above, we estimate GGB France’s reasonably possible range of loss associated with this matter to be approximately 0.4 million EUR to 6.6 million EUR plus a potential undetermined amount of apportioned proceeding expenses, with no amount within the range being a better estimate than the minimum of the range. Accordingly, GGB France has retained the accrual of 0.4 million EUR associated with this matter, which was established in the second quarter of 2016. Asbestos Insurance Coverage Under the Consensual Settlement and Joint Plan described above in Note 20, “Subsidiary Asbestos Bankruptcies,” GST and OldCo retained their rights to seek reimbursement under insurance policies for any amounts they have paid in the past to resolve asbestos claims, including contributions made to the Trust under the Joint Plan. These policies include a number of primary and excess general liability insurance policies that were purchased by Coltec and were in effect prior to January 1, 1976 (the “Pre-Garlock Coverage Block”). The policies provide coverage for “occurrences” happening during the policy periods and cover losses associated with product liability claims against Coltec and certain of its subsidiaries. Asbestos claims against GST are not covered under these policies because GST was not a Coltec subsidiary prior to 1976. The Joint Plan provides that OldCo may retain the first $25 million of any settlements and judgments related to insurance policies in the Pre-Garlock Coverage Block and OldCo and the Trust will share equally in any settlements and judgments OldCo may collect in excess of $25 million . As of December 31, 2017, approximately $44.4 million of available products hazard limits or insurance receivables existed under primary and excess general liability insurance policies other than the Pre-Garlock Coverage Block (the “Garlock Coverage Block”) from solvent carriers with investment grade ratings. On June 12, 2017, the District Court approved several settlements with insurance carriers. First, with respect to available products hazard limits and insurance receivables covering claims against both GST and OldCo under the Garlock Coverage Block, the District Court approved settlements with two carriers that will pay their full aggregate remaining policy limits of approximately $18.8 million over a three-year period following consummation of the Joint Plan; as of December 31, 2017, approximately $14.2 million is due from the two carriers. A previously disclosed agreement with another group of carriers calls for the payment of $11 million . EnPro expects that the full amount of remaining policy limits and insurance receivables (approximately $19.2 million ) in the Garlock Coverage Block will be received either through settlements or in reimbursement of GST’s plan funding as payments are made by the Trust. In addition, the District Court approved settlements with two insurance carriers in the Pre-Garlock Coverage Block that permit the recovery of some of OldCo’s contributions to the Trust under the Joint Plan. Under the settlements, the two carriers were obligated to make one-time cash payments to OldCo in the aggregate amount of approximately $19.0 million within 30 days of consummation of the Joint Plan, which payments were made in August 2017. In addition, the District Court approved a settlement with the successors to Coltec’s Fairbanks Morse Pump business in which the Fairbanks Morse Pump successors agreed to pay OldCo $6 million in three installments over nine years following consummation of the Joint Plan, with the successor entities being entitled to recoup up to the full amount of their payments to OldCo from collections expected to be received from an additional insurance carrier that issued general liability policies to Coltec prior to January 1, 1976. OldCo and the Trust will share equally in any collections above that $6 million amount. OldCo estimates that the carrier will owe approximately $11 million in reimbursements over the life of the Trust for its share of Coltec claims (which includes Fairbanks Morse Pump claims). In August 2017, the Fairbanks Morse Pump successors and EnPro Holdings, as the successor to OldCo, agreed to permit accelerated settlements of the installments upon the lump sum payment of $3 million made to EnPro Holdings in August 2017, with the Fairbanks Morse Pump successors surrendering any right to recoup the amount of such payment from the additional insurance carrier that issued general liability policies to Coltec prior to January 1, 1976. At December 31, 2017 , we had $44.4 million of insurance coverage we believe is available to cover GST asbestos claims payments and certain expense payments, including contributions to the Trust. GST has collected insurance payments totaling $152.3 million since the GST Petition Date. We consider the $44.4 million of available insurance coverage remaining to be of high quality because the insurance policies are written or guaranteed by U.S.-based carriers whose credit rating by S&P is investment grade (BBB-) or better, and whose AM Best rating is excellent (A-) or better. Of the company's $44.4 million remaining solvent insurance coverage, $17.8 million is allocated to claims that were paid by GST LLC prior to the initiation of the Chapter 11 proceedings and submitted to insurance companies for reimbursement, and the remaining $26.6 million is available to pending and estimated future claims. There are specific agreements in place with carriers covering $29.4 million of the remaining available coverage. Based on those agreements and the terms of the policies in place and prior decisions concerning coverage, we believe that all of the $44.4 million of insurance proceeds will ultimately be collected, although there can be no assurance that the insurance companies will make the payments as and when due. Based on those agreements and policies, some of which define specific annual amounts to be paid and others of which limit the amount that can be recovered in any one year, we anticipate that $ 15.0 million will be received either through settlements or in reimbursements of GST's plan funding as payments are made by the asbestos trust. Assuming the insurers pay according to the agreements and policies, we anticipate that the following amounts should be collected in the years set out below: 2018 – $16.8 million 2019 – $5.9 million 2020 – $2.5 million We are a party to legal proceedings initiated in August 2017 in the District Court with two insurers that collectively provide $15 million of coverage under the Garlock Coverage Block. The legal proceedings were initiated by one of the insurers seeking to compel arbitration of issues under its policy and, alternatively, a determination that its policy does not cover asbestos claims. We have counterclaimed, seeking a determination that the policy covers asbestos claims and that the insurer breached the terms of its policy by failing to provide coverage for these claims. We joined the second insurer in this action and are seeking similar relief against it. On October 12, 2017, the magistrate judge issued a decision denying the petitioning insurer's motion to compel arbitration and holding that the arbitration clause in the policy was deleted by an endorsement. The insurer filed an objection to the magistrate judge's decision with the District Court. The District Court has not yet issued a ruling on the objection. GST LLC has received $8.8 million of insurance recoveries from insolvent carriers since 2007, and may receive additional payments from insolvent carriers in the future. No anticipated insolvent carrier collections are included in the $44.4 million of anticipated collections. The insurance available to cover current and future asbestos claims is from comprehensive general liability policies that cover OldCo, as the successor to Coltec, and certain of its other subsidiaries in addition to GST LLC for periods prior to 1985 and therefore could be subject to potential competing claims of other covered subsidiaries and their assignees. Other Commitments We have a number of operating leases primarily for real estate, equipment and vehicles. Operating lease arrangements are generally utilized to secure the use of assets if the terms and conditions of the lease or the nature of the asset makes the lease arrangement more favorable than a purchase. Future minimum lease payments by year and in the aggregate, under noncancelable operating leases with initial or remaining noncancelable lease terms in excess of one year, consisted of the following at December 31, 2017 (in millions): 2018 $ 12.3 2019 10.6 2020 9.0 2021 6.8 2022 5.3 Thereafter 5.4 Total minimum payments $ 49.4 Net rent expense was $12.2 million , $12.6 million and $14.3 million for the years ended December 31, 2017 , 2016 and 2015 , respectively.

Supplemental Guarantor Financia

Supplemental Guarantor Financial Information	12 Months Ended
	Dec. 31, 2017
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Supplemental Guarantor Financial Information	22. Supplemental Guarantor Financial Information In September 2014, we completed the offering of our Senior Notes and, in March 2017, we completed the offering of the Additional Notes. Under the indenture governing the Senior Notes and the Additional Notes, they are together a single series of notes (the "Notes"). The Notes are fully and unconditionally guaranteed on an unsecured, unsubordinated, joint and several basis by our existing and future 100% owned direct and indirect domestic subsidiaries that are each guarantors of our Revolving Credit Facility (collectively, the “Guarantor Subsidiaries”). Our subsidiaries organized outside of the United States, (collectively, the “Non-Guarantor Subsidiaries”) do not guarantee the Notes. A Guarantor Subsidiary's guarantee is subject to release in certain circumstances, including (i) the sale, disposition, exchange or other transfer (including through merger, consolidation, amalgamation or otherwise) of the capital stock of the subsidiary made in a manner not in violation of the indenture governing the Notes; (ii) the designation of the subsidiary as an “Unrestricted Subsidiary” under the indenture governing the Notes; (iii) the legal defeasance or covenant defeasance of the Notes in accordance with the terms of the indenture; or (iv) the subsidiary ceasing to be a subsidiary of the Company as a result of any foreclosure of any pledge or security interest securing our Revolving Credit Facility or other exercise of remedies in respect thereof. The following tables present condensed consolidating financial information for EnPro Industries, Inc. (the "Parent"), the Guarantor Subsidiaries on a combined basis, the Non-Guarantor Subsidiaries on a combined basis and the eliminations necessary to arrive at our consolidated results. The consolidating financial information reflects our investments in subsidiaries using the equity method of accounting. These tables are not intended to present our results of operations, cash flows or financial condition for any purpose other than to comply with the specific requirements for subsidiary guarantor reporting. ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS Year Ended December 31, 2017 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated Net sales $ — $ 921.9 $ 497.3 $ (109.6 ) $ 1,309.6 Cost of sales — 644.6 330.2 (109.6 ) 865.2 Gross profit — 277.3 167.1 — 444.4 Operating expenses: Selling, general and administrative 33.1 183.0 110.2 — 326.3 Other 1.1 12.1 3.7 — 16.9 Total operating expenses 34.2 195.1 113.9 — 343.2 Operating income (loss) (34.2 ) 82.2 53.2 — 101.2 Interest income (expense), net (25.4 ) (24.1 ) 0.1 — (49.4 ) Gain on reconsolidation of GST and OldCo — 534.4 — — 534.4 Other expense, net — (8.7 ) — — (8.7 ) Income (loss) before income taxes (59.6 ) 583.8 53.3 — 577.5 Income tax benefit (expense) 17.6 (20.7 ) (34.6 ) — (37.7 ) Income (loss) before equity in earnings of subsidiaries (42.0 ) 563.1 18.7 — 539.8 Equity in earnings of subsidiaries, net of tax 581.8 18.7 — (600.5 ) — Net income $ 539.8 $ 581.8 $ 18.7 $ (600.5 ) $ 539.8 ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME Year Ended December 31, 2017 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated Net income $ 539.8 $ 581.8 $ 18.7 $ (600.5 ) $ 539.8 Other comprehensive income: Foreign currency translation adjustments 14.4 14.4 14.4 (28.8 ) 14.4 Pension and post-retirement benefits adjustment (excluding amortization) 5.2 5.2 1.3 (6.5 ) 5.2 Amortization of pension and post-retirement benefits included in net income 7.7 7.7 0.1 (7.8 ) 7.7 Other comprehensive income, before tax 27.3 27.3 15.8 (43.1 ) 27.3 Income tax expense related to items of other comprehensive income (4.8 ) (4.8 ) (0.4 ) 5.2 (4.8 ) Other comprehensive income, net of tax 22.5 22.5 15.4 (37.9 ) 22.5 Comprehensive income $ 562.3 $ 604.3 $ 34.1 $ (638.4 ) $ 562.3 ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS Year Ended December 31, 2016 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated Net sales $ — $ 829.0 $ 439.7 $ (81.0 ) $ 1,187.7 Cost of sales — 582.4 291.6 (81.0 ) 793.0 Gross profit — 246.6 148.1 — 394.7 Operating expenses: Selling, general and administrative 27.7 164.0 112.1 — 303.8 Asbestos settlement — 80.0 — — 80.0 Other 4.8 3.3 7.5 — 15.6 Total operating expenses 32.5 247.3 119.6 — 399.4 Operating income (loss) (32.5 ) (0.7 ) 28.5 — (4.7 ) Interest expense, net (18.5 ) (36.2 ) (0.4 ) — (55.1 ) Other expense, net — (8.4 ) (0.5 ) — (8.9 ) Income (loss) before income taxes (51.0 ) (45.3 ) 27.6 — (68.7 ) Income tax benefit (expense) 17.6 21.7 (10.7 ) — 28.6 Income (loss) before equity in earnings of subsidiaries (33.4 ) (23.6 ) 16.9 — (40.1 ) Equity in earnings of subsidiaries, net of tax (6.7 ) 16.9 — (10.2 ) — Net income (loss) $ (40.1 ) $ (6.7 ) $ 16.9 $ (10.2 ) $ (40.1 ) ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME Year Ended December 31, 2016 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated Net income (loss) $ (40.1 ) $ (6.7 ) $ 16.9 $ (10.2 ) $ (40.1 ) Other comprehensive income (loss): Foreign currency translation adjustments (16.3 ) (16.3 ) (16.3 ) 32.6 (16.3 ) Pension and post-retirement benefits adjustment (excluding amortization) (7.8 ) (8.3 ) 0.6 7.7 (7.8 ) Amortization of pension and post-retirement benefits included in net income (loss) 6.9 6.6 0.2 (6.8 ) 6.9 Other comprehensive loss, before tax (17.2 ) (18.0 ) (15.5 ) 33.5 (17.2 ) Income tax expense related to items of other comprehensive income (loss) 0.4 0.5 (0.2 ) (0.3 ) 0.4 Other comprehensive loss, net of tax (16.8 ) (17.5 ) (15.7 ) 33.2 (16.8 ) Comprehensive income (loss) $ (56.9 ) $ (24.2 ) $ 1.2 $ 23.0 $ (56.9 ) ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS Year Ended December 31, 2015 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated Net sales $ — $ 837.8 $ 428.1 $ (61.5 ) $ 1,204.4 Cost of sales — 591.6 278.8 (61.5 ) 808.9 Gross profit — 246.2 149.3 — 395.5 Operating expenses: Selling, general and administrative 27.6 157.1 118.1 — 302.8 Goodwill and other intangible asset impairment — 5.6 41.4 — 47.0 Other 1.8 1.2 5.1 — 8.1 Total operating expenses 29.4 163.9 164.6 — 357.9 Operating income (loss) (29.4 ) 82.3 (15.3 ) — 37.6 Interest income (expense), net (13.1 ) (38.8 ) (0.2 ) — (52.1 ) Other expense, net (2.8 ) (1.3 ) — — (4.1 ) Income (loss) before income taxes (45.3 ) 42.2 (15.5 ) — (18.6 ) Income tax benefit (expense) 12.1 (9.5 ) (4.9 ) — (2.3 ) Income (loss) before equity in earnings of subsidiaries (33.2 ) 32.7 (20.4 ) — (20.9 ) Equity in earnings of subsidiaries, net of tax 12.3 (20.4 ) — 8.1 — Net income (loss) $ (20.9 ) $ 12.3 $ (20.4 ) $ 8.1 $ (20.9 ) ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME Year Ended December 31, 2015 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated Net income $ (20.9 ) $ 12.3 $ (20.4 ) $ 8.1 $ (20.9 ) Other comprehensive income (loss): Foreign currency translation adjustments (21.9 ) (21.9 ) (21.9 ) 43.8 (21.9 ) Pension and post-retirement benefits adjustment (excluding amortization) (3.4 ) (3.6 ) 0.5 3.1 (3.4 ) Amortization of pension and post-retirement benefits included in net income 7.1 7.1 0.2 (7.3 ) 7.1 Other comprehensive loss, before tax (18.2 ) (18.4 ) (21.2 ) 39.6 (18.2 ) Income tax benefit related to items of other comprehensive loss (1.8 ) (1.7 ) (0.2 ) 1.9 (1.8 ) Other comprehensive loss, net of tax (20.0 ) (20.1 ) (21.4 ) 41.5 (20.0 ) Comprehensive loss $ (40.9 ) $ (7.8 ) $ (41.8 ) $ 49.6 $ (40.9 ) ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS Year Ended December 31, 2017 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES $ (106.5 ) $ 61.9 $ 91.3 $ (0.1 ) $ 46.6 INVESTING ACTIVITIES Purchases of property, plant and equipment — (28.2 ) (12.8 ) — (41.0 ) Payments for capitalized internal-use software — (3.6 ) (0.1 ) — (3.7 ) Payments for acquisitions — (39.5 ) (5.1 ) — (44.6 ) Reconsolidation of GST and OldCo — 41.1 — — 41.1 Deconsolidation of OldCo — (4.8 ) — — (4.8 ) Capital contribution to OldCo — (45.2 ) — — (45.2 ) Other — — 0.5 — 0.5 Net cash used in investing activities — (80.2 ) (17.5 ) — (97.7 ) FINANCING ACTIVITIES Net payments between subsidiaries (12.1 ) 19.3 (7.2 ) — — Intercompany dividends — — (0.1 ) 0.1 — Proceeds from debt 151.5 480.7 3.5 — 635.7 Repayments of debt — (482.5 ) (1.8 ) — (484.3 ) Repurchase of common stock (11.5 ) — — — (11.5 ) Dividends paid (19.0 ) — — — (19.0 ) Other (2.4 ) — — — (2.4 ) Net cash provided by (used in) financing activities 106.5 17.5 (5.6 ) 0.1 118.5 Effect of exchange rate changes on cash and cash equivalents — — 10.4 — 10.4 Net increase (decrease) in cash and cash equivalents — (0.8 ) 78.6 — 77.8 Cash and cash equivalents at beginning of year — 0.8 110.7 — 111.5 Cash and cash equivalents at end of year $ — $ — $ 189.3 $ — $ 189.3 ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS Year Ended December 31, 2016 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES $ (45.9 ) $ 82.9 $ 39.7 $ (12.2 ) $ 64.5 INVESTING ACTIVITIES Purchases of property, plant and equipment — (28.4 ) (7.4 ) — (35.8 ) Payments for capitalized internal-use software — (3.8 ) (0.3 ) — (4.1 ) Proceeds from sale of business — 2.9 3.7 — 6.6 Payments for acquisitions — (25.5 ) (3.0 ) — (28.5 ) Other — — 0.4 — 0.4 Net cash used in investing activities — (54.8 ) (6.6 ) — (61.4 ) FINANCING ACTIVITIES Net payments between subsidiaries 96.6 (95.6 ) (1.0 ) — — Intercompany dividends — — (12.2 ) 12.2 — Proceeds from debt — 344.7 6.1 — 350.8 Repayments of debt — (277.1 ) (1.0 ) — (278.1 ) Repurchase of common stock (30.4 ) — — — (30.4 ) Dividends paid (18.1 ) — — — (18.1 ) Other (2.2 ) — — — (2.2 ) Net cash provided by (used in) financing activities 45.9 (28.0 ) (8.1 ) 12.2 22.0 Effect of exchange rate changes on cash and cash equivalents — — (17.0 ) — (17.0 ) Net increase in cash and cash equivalents — 0.1 8.0 — 8.1 Cash and cash equivalents at beginning of year — 0.7 102.7 — 103.4 Cash and cash equivalents at end of year $ — $ 0.8 $ 110.7 $ — $ 111.5 ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS Year Ended December 31, 2015 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES $ (25.6 ) $ 77.5 $ 35.1 $ (0.5 ) $ 86.5 INVESTING ACTIVITIES Purchases of property, plant and equipment — (23.0 ) (13.8 ) — (36.8 ) Payments for capitalized internal-use software — (4.6 ) — — (4.6 ) Payments for acquisitions — (42.4 ) (3.1 ) — (45.5 ) Other — 0.1 0.3 — 0.4 Net cash used in investing activities — (69.9 ) (16.6 ) — (86.5 ) FINANCING ACTIVITIES Net payments between subsidiaries 178.1 (183.9 ) 5.8 — — Intercompany dividends — — (0.5 ) 0.5 — Proceeds from debt — 225.0 5.8 — 230.8 Repayments of debt (25.5 ) (162.9 ) (0.6 ) — (189.0 ) Repurchase of common stock (85.3 ) — — — (85.3 ) Dividends paid (18.0 ) — — — (18.0 ) Repurchase of convertible debentures conversion option (21.6 ) — — — (21.6 ) Other (2.1 ) — — — (2.1 ) Net cash provided by (used in) financing activities 25.6 (121.8 ) 10.5 0.5 (85.2 ) Effect of exchange rate changes on cash and cash equivalents — — (5.6 ) — (5.6 ) Net increase (decrease) in cash and cash equivalents — (114.2 ) 23.4 — (90.8 ) Cash and cash equivalents at beginning of year — 114.9 79.3 — 194.2 Cash and cash equivalents at end of year $ — $ 0.7 $ 102.7 $ — $ 103.4 ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING BALANCE SHEETS December 31, 2017 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated ASSETS Current assets Cash and cash equivalents $ — $ — $ 189.3 $ — $ 189.3 Accounts receivable, net — 180.1 81.6 — 261.7 Intercompany receivables — 24.0 6.7 (30.7 ) — Inventories — 135.4 68.7 — 204.1 Income tax receivable 132.3 1.3 2.0 (22.4 ) 113.2 Prepaid expenses and other current assets 4.3 26.5 20.5 — 51.3 Total current assets 136.6 367.3 368.8 (53.1 ) 819.6 Property, plant and equipment, net — 206.8 90.1 — 296.9 Goodwill — 261.0 75.1 — 336.1 Other intangible assets, net — 284.2 62.8 — 347.0 Intercompany receivables — 22.9 — (22.9 ) — Investment in subsidiaries 1,261.3 460.1 — (1,721.4 ) — Other assets 12.8 59.3 14.4 — 86.5 Total assets $ 1,410.7 $ 1,661.6 $ 611.2 $ (1,797.4 ) $ 1,886.1 LIABILITIES AND EQUITY Current liabilities Current maturities of long-term debt $ — $ 0.2 $ — $ — $ 0.2 Accounts payable 2.3 82.5 45.9 — 130.7 Intercompany payables — 6.7 24.0 (30.7 ) — Accrued expenses 22.8 90.1 46.7 (22.4 ) 137.2 Total current liabilities 25.1 179.5 116.6 (53.1 ) 268.1 Long-term debt 444.2 174.1 — — 618.3 Intercompany payables 22.9 — — (22.9 ) — Other liabilities 15.7 46.7 34.5 — 96.9 Total liabilities 507.9 400.3 151.1 (76.0 ) 983.3 Shareholders’ equity 902.8 1,261.3 460.1 (1,721.4 ) 902.8 Total liabilities and equity $ 1,410.7 $ 1,661.6 $ 611.2 $ (1,797.4 ) $ 1,886.1 ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING BALANCE SHEETS As of December 31, 2016 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated ASSETS Current assets Cash and cash equivalents $ — $ 0.8 $ 110.7 $ — $ 111.5 Accounts receivable, net 0.2 151.2 56.7 — 208.1 Intercompany receivables — 10.2 4.7 (14.9 ) — Inventories — 125.9 49.5 — 175.4 Prepaid expenses and other current assets 21.3 8.9 17.4 (17.7 ) 29.9 Total current assets 21.5 297.0 239.0 (32.6 ) 524.9 Property, plant and equipment, net 0.1 148.5 66.8 — 215.4 Goodwill — 175.5 26.0 — 201.5 Other intangible assets, net — 156.5 20.4 — 176.9 Investment in GST — 236.9 — — 236.9 Intercompany receivables — 43.6 1.5 (45.1 ) — Investment in subsidiaries 681.1 236.4 — (917.5 ) — Other assets 16.4 156.2 18.2 — 190.8 Total assets $ 719.1 $ 1,450.6 $ 371.9 $ (995.2 ) $ 1,546.4 LIABILITIES AND EQUITY Current liabilities Short-term borrowings from GST $ — $ — $ 26.2 $ — $ 26.2 Notes payable to GST — 12.7 — — 12.7 Current maturities of long-term debt — 0.2 — — 0.2 Accounts payable 2.3 61.9 38.7 — 102.9 Intercompany payables — 4.7 10.2 (14.9 ) — Accrued expenses 15.3 130.1 33.3 (17.7 ) 161.0 Total current liabilities 17.6 209.6 108.4 (32.6 ) 303.0 Long-term debt 294.1 130.7 — — 424.8 Notes payable to GST — 283.2 — — 283.2 Intercompany payables 35.0 1.4 8.7 (45.1 ) — Other liabilities 13.9 144.6 18.4 — 176.9 Total liabilities 360.6 769.5 135.5 (77.7 ) 1,187.9 Shareholders’ equity 358.5 681.1 236.4 (917.5 ) 358.5 Total liabilities and equity $ 719.1 $ 1,450.6 $ 371.9 $ (995.2 ) $ 1,546.4

Selected Quarterly Financial Da

Selected Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data (Unaudited)	23. Selected Quarterly Financial Data (Unaudited) First Quarter (1) Second Quarter Third Quarter (1) Fourth Quarter (1) (in millions, except per share data) 2017 2016 2017 2016 2017 2016 2017 2016 Net sales $ 295.8 $ 294.9 $ 307.6 $ 313.2 $ 343.7 $ 292.7 $ 362.5 $ 286.9 Gross profit $ 101.6 $ 97.6 $ 104.5 $ 107.9 $ 115.2 $ 98.6 $ 123.1 $ 90.6 Net income (loss) $ 6.4 $ (46.8 ) $ 9.0 $ 3.6 $ 490.2 $ 6.0 $ 34.2 $ (2.9 ) Basic earnings (loss) per share $ 0.30 $ (2.15 ) $ 0.42 $ 0.17 $ 22.98 $ 0.28 $ 1.60 $ (0.14 ) Diluted earnings (loss) per share $ 0.30 $ (2.15 ) $ 0.41 $ 0.17 $ 22.49 $ 0.28 $ 1.57 $ (0.14 ) (1) Items impacting comparability of net income and earnings (loss) per share in these quarters included: • An $80.0 million recorded by EnPro in the first quarter of 2016 in association with the Joint Plan to resolve current and future asbestos claims (see Note 2, "Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC") • The $534.4 million gain recorded on the reconsolidation of GST and OldCo in the third quarter of 2017 (See Note 2), and the tax impacts of the reconsolidation recorded in that quarter (See Note 5, "Income Taxes") • The impacts of the Tax Act recorded in the fourth quarter of 2017 (See Note 5)

SCHEDULE II - Valuation and Qua

SCHEDULE II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
SCHEDULE II - Valuation and Qualifying Accounts	SCHEDULE II Valuation and Qualifying Accounts For the Years Ended December 31, 2017 , 2016 and 2015 (in millions) Allowance for Doubtful Accounts Balance, Beginning of Year Charge (credit) to Expense Write-off of Receivables Other (1) Balance, End of Year 2017 $ 4.9 $ 1.2 $ (1.6 ) $ 0.2 $ 4.7 2016 $ 5.4 $ 1.1 $ (1.6 ) $ — $ 4.9 2015 $ 7.0 $ (0.2 ) $ (1.4 ) $ — $ 5.4 (1) Consists primarily of the effect of changes in currency rates. Deferred Income Tax Valuation Allowance Balance, Beginning of Year Charge (credit) to Expense Expiration of Net Operating Losses Other (2) Balance, End of Year 2017 $ 20.2 $ 1.2 $ (0.1 ) $ 4.4 $ 25.7 2016 $ 17.6 $ 4.6 $ (0.1 ) $ (1.9 ) $ 20.2 2015 $ 19.9 $ 0.4 $ (0.1 ) $ (2.6 ) $ 17.6 (2) Consists primarily of the effects of changes in currency rates and statutory changes in tax rates.

Overview, Basis of presentati32

Overview, Basis of presentation, Significant Accounting Policies and Recently Issued Accounting Guidance (Policies)	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Revenue Recognition	Revenue Recognition – For the Sealing Products and Engineered Products segments, revenue is recognized at the time title and risk of product ownership is transferred or when services are rendered, typically when product is shipped or delivered, depending on the terms of the sale agreement. Shipping costs billed to customers are recognized as revenue and expensed in cost of goods sold since they are fixed and determinable and collection is reasonably assured. We generally use the percentage-of-completion (“POC”) accounting method to account for our long-term contracts associated with the design, development, manufacture, or modification of complex engines under fixed price or cost plus contracts. During the third quarter of 2011, the Power Systems segment began using POC for prospective engine contracts. We made this change because, as a result of enhancements to our financial management and reporting systems, we are able to reasonably estimate the revenue, costs, and progress towards completion of engine builds. If we are not able to meet those conditions for a particular engine contract, we recognize revenues using the completed-contract method. Additionally, engines that were in production at June 30, 2011 continued to use the completed-contract method through completion and shipment. Under POC, revenue is recognized based on the extent of progress towards completion of the long-term contract. We generally use the cost-to-cost measure for our long-term contracts unless we believe another method more clearly measures progress towards completion of the contract. Under the cost-to-cost measure, the extent of progress towards completion is measured based on the ratio of costs incurred to date to the total estimated costs at completion of the contract. Contract costs include labor, material and subcontracting costs, as well as an allocation of indirect costs. Revenues, including estimated fees or profits, are recorded as costs are incurred. Due to the nature of the work required to be performed on many of our contracts, the estimation of total revenue and cost at completion is complex and subject to many variables. Management must make assumptions and estimates regarding labor productivity including the benefits of learning and investments in new technologies, the complexity of the work to be performed, the availability and future prices of materials, the length of time to complete the contract (to estimate increases in wages and prices for materials and related support cost allocations), performance by our subcontractors and overhead cost rates, among other variables. Based on our analysis, any quarterly adjustments to net sales, cost of sales, and the related impact to operating income are recognized in the period they become known. These adjustments may result in an increase or a decrease in operating income. Changes in estimates of net sales, cost of sales, and the related impact to operating income are recognized quarterly on a cumulative catch-up basis, which recognizes in the current period the cumulative effect of the changes on current and prior periods based on a contract's percentage of completion. A significant change in one or more of these estimates could affect the profitability of one or more of our contracts. When estimates of total costs to be incurred on a contract exceed total estimates of revenue to be earned, a provision for the entire loss on the contract is recorded in the period the loss is determined. Contracts accounted for under the POC method represented revenues and margins of $76.3 million and $12.9 million , respectively, for the year ended December 31, 2017 , $86.3 million and $6.9 million , respectively, for the year ended December 31, 2016 , and $67.3 million and $8.9 million , respectively, for the year ended December 31, 2015 .
Foreign Currency Translation	Foreign Currency Translation – The financial statements of those operations whose functional currency is a foreign currency are translated into U.S. dollars using the current rate method. Under this method, all assets and liabilities are translated into U.S. dollars using current exchange rates, and income statement activities are translated using average exchange rates. The foreign currency translation adjustment is included in accumulated other comprehensive loss in the Consolidated Balance Sheets. Gains and losses on foreign currency transactions are included in operating income. Foreign currency transaction gains totaled $1.2 million , $ 1.5 million , and $1.8 million respectively, in 2017 and 2016 , and 2015 .
Research and Development Expense	Research and Development Expense – Costs related to research and development activities are expensed as incurred. We perform research and development primarily under Company-funded programs for commercial products. Research and development expenditures in 2017 , 2016 , and 2015 were $32.7 million , $28.9 million , and $22.5 million , respectively, and are included in selling, general and administrative expenses in the Consolidated Statements of Operations.
Income Taxes	Income Taxes – We use the asset and liability method of accounting for income taxes. Temporary differences arising between the tax basis of an asset or liability and its carrying amount on the Consolidated Balance Sheet are used to calculate future income tax assets or liabilities. This method also requires the recognition of deferred tax benefits, such as net operating loss carryforwards. A valuation allowance is recorded to reduce deferred tax assets when it is more likely than not that a tax benefit will not be realized. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to the taxable income (losses) in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the date of enactment of the change. A tax benefit from an uncertain tax position is recognized only if we believe it is more likely than not that the position will be sustained on its technical merits. If the recognition threshold for the tax position is met, only the portion of the tax benefit that we believe is greater than 50 percent likely to be realized is recorded. On December 22, 2017, the Tax Cuts and Jobs Act (the "Tax Act") was enacted and contains several key tax provisions impacting the Company including the reduction of the corporate income tax rate from 35.0% to 21.0% , the transition to a territorial tax system and a mandatory one-time transition tax on accumulated earnings of foreign subsidiaries. The impact of these tax law changes, including the remeasurement of our deferred tax assets and liabilities based on the tax rates in effect at the time the deferred balances are expected to reverse, the reassessment of the net realizability of the deferred tax balances, and the transition tax, are required to be recognized in our income tax provision in the fourth quarter 2017, the period of enactment. In December 2017, U.S. Securities and Exchange Commission ("SEC") issued guidance to address the application of authoritative tax accounting guidance in situations where companies do not have the necessary information available, prepared, or analyzed in reasonable detail to complete the accounting for certain income tax effects of the Tax Act for the reporting period in which the Tax Act was enacted. In these instances, the SEC's guidance allows us to record provisional amounts during a measurement period not to extend beyond one year of the enactment date. Since the Tax Act was passed at the end of 2017, and ongoing guidance and interpretation is expected over the next twelve months, we consider the impact of the transition tax, remeasurement of deferred tax assets and liabilities, and other items recorded in our year-end income tax provision to be a reasonable estimate, but provisional, subject to further analysis of year-end data and refinement of the Company’s calculations. We expect to complete our analysis within the one-year measurement period in accordance with the SEC's guidance. Please see Note 5, "Income Taxes" for further information on the provisional items recorded in 2017.
Cash and Cash Equivalents	Cash and Cash Equivalents – Cash and cash equivalents include cash on hand, demand deposits and highly liquid investments with a maturity of three months or less at the time of purchase.
Receivables	Receivables – Accounts receivable are stated at the historical carrying amount net of write-offs and allowance for doubtful accounts. We establish an allowance for doubtful accounts receivable based on historical experience and any specific customer collection issues we have identified. Doubtful accounts receivable are written off when a settlement is reached for an amount less than the outstanding historical balance or when we have determined the balance will not be collected. The balances billed but not paid by customers pursuant to retainage provisions in long-term contracts and programs are normally due upon completion of the contracts and/or acceptance by the owner of specified deliverables. At December 31, 2017 , we had $0.3 million of retentions expected to be collected in 2018 recorded in accounts receivable and $0.9 million of retentions expected to be collected beyond 2018 recorded in other long-term assets in the Consolidated Balance Sheet. At December 31, 2016 , we had $1.3 million of current retentions and $1.8 million of long-term retentions recorded in the Consolidated Balance Sheet.
Inventories	Inventories – Certain domestic inventories are valued by the last-in, first-out (“LIFO”) cost method. Inventories not valued by the LIFO method, other than inventoried costs relating to long-term contracts and programs, are valued using the first-in, first-out (“FIFO”) cost method, and are recorded at the lower of cost or net realizable value. Approximately 34% and 38% of inventories were valued by the LIFO method in 2017 and 2016 , respectively. Inventoried costs relating to long-term contracts and programs are stated at the actual production cost incurred to date, including direct labor and factory overhead. Progress payments related to long-term contracts and programs accounted for under the completed-contract method of accounting are shown as a reduction of inventories. Initial program start-up costs and other nonrecurring costs are expensed as incurred.
Property, Plant and Equipment	Property, Plant and Equipment – Property, plant and equipment are recorded at cost. Depreciation of plant and equipment is determined on the straight-line method over the following estimated useful lives of the assets: buildings and improvements, 5 to 25 years; machinery and equipment, 3 to 10 years.
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets – Goodwill represents the excess of the purchase price over the estimated fair value of the net assets of acquired businesses, including the reconsolidated GST and OldCo businesses. Goodwill is not amortized, but instead is subject to annual impairment testing conducted each year as of October 1. The goodwill asset impairment test involves comparing the fair value of a reporting unit to its carrying amount. If the carrying amount of a reporting unit exceeds its fair value, a second step of comparing the implied fair value of the reporting unit’s goodwill to the carrying amount of that goodwill is required to measure the potential goodwill impairment loss. Interim tests may be required if an event occurs or circumstances change that would more likely than not reduce the fair value of a reporting unit below its carrying amount. We completed our required annual impairment tests of goodwill as of October 1, 2017 and 2016 . These assessments did not indicate any impairment of the goodwill, and the fair values of each of our reporting units significantly exceeded their carrying values. Through the first quarter of 2015, several initiatives were implemented to remove labor, facility and other costs from CPI’s cost structure and a customer-focused organizational realignment was implemented to identify price and volume opportunities to optimize sales and profitability in the weak oil and gas business environment. During the first quarter of 2015 new strategic options and opportunities to improve business performance were analyzed given the continuing weakness in demand. Additional strategic measures were planned to be implemented during the second half of 2015 and the expected benefits of these actions were taken into consideration in assessing the outlook for CPI. However, as more time passed, the benefits of strategic measures and initiatives being implemented were no longer expected to sufficiently compensate for the financial impacts of the prolonged and significant weakness in the oil and gas markets served by CPI. Taking this into account, the forecasted results for CPI were lowered significantly at the end of May 2015 to such an extent that we thought it likely that the fair value of CPI would be less than its carrying value which necessitated an interim impairment test for goodwill. The interim step one analysis we performed, using a combination of discounted cash flow and market value approaches to determine the fair value of CPI consistent with our annual impairment testing, indicated that the fair value of CPI was less than the carrying value of its net assets. The required step two valuation analysis performed as of May 31, 2015 and completed in July 2015 indicated that $ 46.1 million of the CPI goodwill balance was impaired. Accordingly, CPI goodwill in the amount of $ 46.1 million was written-off in the second quarter of 2015. We completed our required annual impairment test of goodwill as of October 1, 2017, which did not indicate any additional impairment of our goodwill. Other intangible assets are recorded at cost, or when acquired as a part of a business combination (including in the reconsolidation of GST and OldCo as it was treated as a business acquisition under applicable accounting rules), at estimated fair value. These assets include customer relationships, patents and other technology agreements, trademarks, licenses and non-compete agreements. Intangible assets that have definite lives are amortized using a method that reflects the pattern in which the economic benefits of the assets are consumed or the straight-line method over estimated useful lives of 2 to 21 years. Intangible assets with indefinite lives are subject to at least annual impairment testing, which compares the fair value of the intangible asset with its carrying amount using the relief from royalty method. Other than as described above, the results of our assessments did not indicate any impairment to our indefinite-lived intangible assets for the years presented. We review the carrying amounts of long-lived assets when certain events or changes in circumstances indicate that the carrying amounts may not be recoverable. In consideration of the poor financial performance of the ATDynamics business, an asset group in the Stemco division of our Sealing Products segment, for the quarter ended September 30, 2017 and significantly lowered expectations for the fourth quarter forecast and the budget for fiscal year 2018, we determined that a test of ATDynamics' recoverability was required. An impairment loss is recognized when the carrying amount of the asset group is not recoverable and exceeds its fair value. We estimate the fair values of assets subject to long-lived asset impairment based on our own judgments about the assumptions that market participants would use in pricing the assets. In doing so, we used an income approach based upon discounted cash flows. The key assumptions used for the discounted cash flow approach include expected cash flows based on internal business plans, projected growth rates, discount rates, and royalty rates for certain intangible assets. We classified these fair value measurements as Level 3. As a result of this test, certain of ATDynamics' definite-lived intangible assets were determined to be impaired, and were valued in total at $1.7 million , resulting in an impairment loss of $10.1 million , which equaled the excess of these assets' net book value at September 30, 2017 over their fair value. The loss is reflected in Goodwill and other intangible asset impairment in the Consolidated Statement of Operations. Additionally, during the year ended December 31, 2017, we determined that approximately $1.8 million of amortized customer relationship intangibles associated with certain smaller locations that we exited in 2017 would no longer provide continuing value to us as a result of the exits. Therefore, these assets were written off. As these write-offs relate to restructuring activities, this amount is presented in other operating expense in the Consolidated Statement of Operations for the year ended December 31, 2017. During the year ended December 31, 2015, we determined $0.9 million of amortized trademarks associated with CPI were impaired and therefore were written off. This amount is included in goodwill and other intangible asset impairment in the accompanying Consolidated Statement of Operations for the year ended December 31, 2015.
Investment in GST	Investment in GST – The historical business operations of Garlock Sealing Technologies LLC (“GST LLC”) and The Anchor Packing Company (“Anchor”) have resulted in a substantial volume of asbestos litigation in which plaintiffs have alleged personal injury or death as a result of exposure to asbestos fibers. Those subsidiaries manufactured and/or sold industrial sealing products, predominately gaskets and packing, that contained encapsulated asbestos fibers. Anchor was an inactive and insolvent indirect subsidiary. Our subsidiaries’ exposure to asbestos litigation and their relationships with insurance carriers have been managed through another Coltec subsidiary, Garrison Litigation Management Group, Ltd. (“Garrison”). GST LLC, Anchor and Garrison are collectively referred to as “GST.” On June 5, 2010 (the “GST Petition Date”), GST LLC, Anchor and Garrison filed voluntary petitions for reorganization under Chapter 11 of the United States Bankruptcy Code in the U.S. Bankruptcy Court for the Western District of North Carolina in Charlotte (the “Bankruptcy Court”). GST’s financial results were included in our consolidated results through June 4, 2010, the day prior to the GST Petition Date. However, GAAP requires that an entity that files for protection under the U.S. Bankruptcy Code, whether solvent or insolvent, whose financial statements were previously consolidated with those of its parent, as GST and its subsidiaries were with EnPro, generally must be prospectively deconsolidated from the parent and the investment accounted for using the cost method. At deconsolidation, our investment was recorded at its estimated fair value on June 4, 2010. The cost method required us to present our ownership interests in the net assets of GST at the GST Petition Date as an investment and to not recognize any income or loss from GST and subsidiaries in our results of operations during the reorganization period. During the pendency of these proceedings in the Bankruptcy Court, our investment in GST was subject to periodic reviews for impairment. When GST emerged from the supervision of the Bankruptcy Court upon confirmation and effectiveness of a plan of reorganization effective at 12:01 a.m. on July 31, 2017, the investment balance was derecognized as further described in Note 2, "Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC."
Debt	Debt – Debt issuance costs associated with our 5.875% Senior Notes due in 2022 (the “Senior Notes”) that are incremental third party costs of issuing the debt are recognized as a reduction in the carrying value of the debt and amortized into interest expense over the time period to maturity using the interest method. Debt issuance costs associated with our senior secured revolving credit facility (the “Revolving Credit Facility”) are presented as an asset and subsequently amortized ratably over the term of the revolving debt arrangement. In October 2005, we issued $172.5 million in aggregate principal amount of 3.9375% Convertible Senior Debentures (the “Convertible Debentures”), which matured in October 2015. Applicable authoritative accounting guidance required that the liability component of the Convertible Debentures be recorded at its fair value as of the issuance date. This resulted in us recording debt in the amount of $111.2 million as of the issuance date with the $61.3 million offset to the debt discount being recorded in equity on a net of tax basis. The debt discount was amortized through interest expense until the maturity date of October 15, 2015, resulting in an effective interest rate of approximately 9.5% . Interest expense related to the Convertible Debentures for the year ended December 31, 2015 included $0.4 million of contractual interest coupon and $0.2 million of debt discount amortization.
Derivative Instruments	Derivative Instruments – We use derivative financial instruments to manage our exposure to various risks. The use of these financial instruments modifies the exposure with the intent of reducing our risk. We do not use financial instruments for trading purposes, nor do we use leveraged financial instruments. The counterparties to these contractual arrangements are major financial institutions. We use multiple financial institutions for derivative contracts to minimize the concentration of credit risk. The current accounting rules require derivative instruments, excluding certain contracts that are issued and held by a reporting entity that are both indexed to its own stock and classified in shareholders’ equity, be reported in the Consolidated Balance Sheets at fair value and that changes in a derivative’s fair value be recognized currently in earnings unless specific hedge accounting criteria are met. We are exposed to foreign currency risks that arise from normal business operations. These risks include the translation of local currency balances on our foreign subsidiaries’ balance sheets, intercompany loans with foreign subsidiaries and transactions denominated in foreign currencies. We strive to control our exposure to these risks through our normal operating activities and, where appropriate, through derivative instruments. We periodically enter into contracts to hedge forecasted transactions that are denominated in foreign currencies. The notional amount of foreign exchange contracts was $0.5 million and $2.8 million at December 31, 2017 and 2016 , respectively. All contracts outstanding at December 31, 2017 expired in January of 2018. The notional amounts of all of our foreign exchange contracts were recorded at their fair market value as of December 31, 2017 with changes in market value recorded in income. The earnings impact of any foreign exchange contract that is specifically related to the purchase of inventory is recorded in cost of sales and the changes in market value of all other contracts are recorded in selling, general and administrative expense in the Consolidated Statements of Operations. The balances of derivative assets are recorded in other current assets and the balances of derivative liabilities are recorded in accrued expenses in the Consolidated Balance Sheets.
Fair Value Measurements	Fair Value Measurements – Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. We utilize a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three broad levels. The following is a brief description of those three levels: • Level 1: Observable inputs such as quoted prices in active markets for identical assets or liabilities. • Level 2: Inputs other than quoted prices that are observable for the asset or liability, either directly or indirectly. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. • Level 3: Unobservable inputs that reflect our own assumptions. The fair value of intangible assets associated with acquisitions was determined using a discounted cash flow analysis. Projecting discounted future cash flows required us to make significant estimates regarding future revenues and expenses, projected capital expenditures, changes in working capital and the appropriate discount rate. This non-recurring fair value measurement would be classified as Level 3 due to the absence of quoted market prices or observable inputs for assets of a similar nature. Similarly, the fair value computations for the recurring impairment analyses of goodwill and indefinite-lived intangible assets would be classified as Level 3 due to the absence of quoted market prices or observable inputs. The key assumptions used for the discounted cash flow approach include expected cash flows based on internal business plans, projected growth rates and discount rates. Significant changes in any of those inputs could result in a significantly different fair value measurement.
Pension and Other Postretirement Plans, Pensions, Policy [Policy Text Block]	Pensions and Post-retirement Benefits - Amortization of the net gain or loss resulting from experience different from that assumed and from changes in assumptions is included as a component of benefit cost. If, as of the beginning of the year, that net gain or loss exceeds 10% of the greater of the projected benefit obligation or the market-related value of plan assets, the amortization is that excess divided by the average remaining service period of participating employees expected to receive benefits under the plan. We amortize prior service cost using the straight-line basis over the average future service life of active participants. For segment reporting purposes, we allocate service cost and the amortization of prior service cost to each location generating those costs. All other components of net periodic pension cost are allocated based on each segment's projected benefit obligation.
Recently Issued Accounting Guidance	Recently Issued Accounting Guidance In February 2018, a standard was issued that helps organizations address certain stranded income tax effects in accumulated other comprehensive income resulting from the Tax Act. The standard provides financial statement preparers with an option to reclassify stranded tax effects within accumulated other comprehensive income to retained earnings in each period in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Act is recorded. The amendments in this guidance are effective for financial statements issued for interim and annual periods beginning after December 15, 2018, with early adoption permitted. We are currently evaluating the alternatives presented by the standard with respect to the tax effects associated with our pension plan unamortized net losses and service costs that are in our balance of accumulated other comprehensive income. In March 2017, a standard was issued that requires an employer to report the service cost component of pension and other postretirement benefits expense in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period. The other components of net benefit cost are required to be presented in the income statement separately from the service cost component and outside a subtotal of income from operations. The amendments in this standard also allow only the service cost component to be eligible for capitalization when applicable (for example, as a cost of internally manufactured inventory or a self-constructed asset). The standard is effective for fiscal years beginning after December 15, 2017, including interim periods within those annual periods, and is to be applied retrospectively for the classification of pension and other postretirement benefits expense on the income statement and prospectively for the criteria on capitalization of certain costs. For the years ended December 31, 2017 and 2016, the application of this guidance would have resulted in an increase in operating income of approximately $0.5 million and $2.2 million , respectively with a corresponding increase in non-operating expenses. In January 2017, a standard was issued to simplify annual and interim goodwill impairment testing for public business entities. Under the standard, an entity should perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. An entity still has the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. The standard is effective for any interim goodwill impairment tests in fiscal years beginning after December 15, 2019, and is to be applied prospectively. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The standard is not currently expected to have a significant impact on our consolidated financial statements or disclosures. In January 2017, a standard was issued to clarify the definition of a business in determining whether a purchase of an asset or group of assets is to be accounted for as a purchase of a business and thus subject to authoritative guidance on business combinations. The standard narrows the current definition of a business, stating that t o be considered a business, an asset or group of assets must include an input and a substantive process that create outputs. An input is an economic resource, such as intellectual property or employees, used to create the goods or services that are considered outputs. The guidance is effective for fiscal years that begin after December 15, 2017 and is to be applied prospectively. This standard is not expected to have a significant impact on our consolidated financial statements or disclosures. In August 2016, a standard was issued to eliminate diversity in practice in the classification of certain cash receipts and cash payments within the statement of cash flows. The standard is effective for annual periods beginning after December 15, 2017, and interim periods therein. Early adoption is permitted, including adoption in an interim period. The guidance requires application through a retrospective transition method. This standard is not expected to have a significant impact on our consolidated financial statements or disclosures. In June 2016, a standard was issued that significantly changes how entities will measure credit losses for most financial assets and certain other instruments that are not measured at fair value through net income, including trade receivables. The standard requires an entity to estimate its lifetime “expected credit loss” for such assets at inception, and record an allowance that, when deducted from the amortized cost basis of the financial asset, presents the net amount expected to be collected on the financial asset. The standard is effective for annual periods beginning after December 15, 2019, and interim periods therein. Early adoption is permitted for annual periods beginning after December 15, 2018, and interim periods therein. We are currently evaluating the new guidance to determine the impact it will have on our consolidated financial statements. Based upon our current population of receivables and associated historical credit loss experience, we do not expect that this standard will have a significant impact on our consolidated financial statements. This conclusion could be impacted by any significant future financing arrangements that we may choose to enter with customers. In February 2016, a standard was issued to establish principles to report transparent and economically neutral information about the assets and liabilities that arise from leases. The standard will require lessees to recognize the lease assets and lease liabilities that arise from all leases in the statement of financial position and to disclose qualitative and quantitative information about lease transactions, such as information about variable lease payments and options to renew and terminate leases. The standard retains a distinction between finance leases and operating leases. As a result, the effect of leases in the statement of operations and the statement of cash flows is largely unchanged. Additionally, the guidance provides clarification on the definition of a lease, including alignment of the concept of control of an asset with principles in other authoritative guidance around revenue recognition and consolidation. The amendments in this guidance are effective for financial statements issued for interim and annual periods beginning after December 15, 2018, with early adoption permitted. We are currently evaluating the new guidance to determine the impact it will have on our consolidated financial statements. While we do not currently expect that adoption of the standard will have a material impact to our Consolidated Statements of Operations, Comprehensive Income, or Cash Flows, the addition of lease liabilities, and assets of similar amount, to our Consolidated Balance Sheets for leases currently accounted for as operating leases will increase both total assets and liabilities. At December 31, 2017, future minimum lease payments under non-cancelable operating leases were $49.4 million . The amount of increase will depend mainly upon the dollar value of operating lease commitments at the time of adoption, which could change significantly from our current commitments due to factors including lease expirations, future lease versus buy decisions, acquisitions, and divestitures. In January 2016, a standard was issued that amends existing guidance around classification and measurement of certain financial assets and liabilities. Changes to the current GAAP model primarily affect the accounting for equity investments, financial liabilities under the fair value option, and the presentation and disclosure requirements for financial instruments. Under the new guidance, all equity investments in unconsolidated entities (other than those accounted for using the equity method of accounting) will generally be measured at fair value through earnings. For equity investments without readily determinable fair values, the cost method is also eliminated. However, most entities will be able to elect to record equity investments without readily determinable fair values at cost, less impairment, and plus or minus subsequent adjustments for observable price changes. The standard also requires that financial assets and liabilities be disclosed separately in the notes to the financial statements based on measurement principle and form of financial asset. The amendments in this guidance are effective for financial statements issued for interim and annual periods beginning after December 15, 2017. This standard is not expected to have a significant impact on our consolidated financial statements or disclosures. In May 2014, a comprehensive new revenue recognition standard was issued that will supersede nearly all existing revenue recognition guidance. The new guidance introduces a five-step model in which an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. This guidance also requires disclosures sufficient to enable users to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers, including qualitative and quantitative disclosures about contracts with customers, significant judgments and changes in judgments, and assets recognized from the costs to obtain or fulfill a contract. The new standard will become effective for us beginning with the first quarter 2018. The guidance will affect certain aspects of our current practice of accounting for engine contracts in our Power Systems segment. We expect that our long-term contracts will continue to recognize revenue and earnings over time as the work progresses because of the continuous transfer of control to the customer, generally using an input measure (e.g., costs incurred) to reflect progress. Our current practice of accounting for such contracts as single profit centers under existing guidance could change in instances where such contracts are determined to have multiple performance obligations that are distinct within the context of the contract under the new standard. Identifying multiple performance obligations in a contract currently accounted for as a single profit center could make the rate at which we recognize revenue and margins under that contract faster or slower, depending on the contract. Additionally, we have certain service contracts where revenue is currently recognized using a milestone method. Under the new guidance, revenue on such contracts will be recognized more frequently throughout the contract using an input measure. Finally, we have certain limited instances of costs that are currently expensed as incurred at the segment that we believe meet the criteria to be capitalized as incremental costs of obtaining a contract under the new guidance. The new standard provides certain practical expedients that we may elect in adopting and following the new guidance. We plan to utilize a practical expedient that permits us to expense the costs to obtain a contract (such as those discussed above) as incurred when the expected amortization period is one year or less. Another expedient that we plan to elect is to not adjust the promised amount of consideration in contracts for the effects of a significant financing component if the entity expects, at contract inception, that the period between when the entity transfers a promised good or service to the customer and when the customer pays for that good or service will be one year or less. We currently do not have any contracts that would require such consideration, but we do consider new arrangements from time to time that could be affected by this aspect of the guidance. We have made progress in evaluating the new disclosure requirements of the standard. Among the new requirements is one that will have entities provide disaggregation of revenue into categories that show how economic factors affect the nature, amount, timing, and uncertainty of revenue and cash flows. To meet this requirement, we plan to provide information on our revenue from customers in the major end markets with which we do business, as the underlying economic conditions in these various markets are a major driver in our overall sales performance and in year over year comparisons. We will adopt the guidance using the modified retrospective transition alternative provided in the standard, meaning that contracts open during the transition period that will continue beyond the effective date are evaluated for impact in transition to the new guidance. Based upon review of our current contract portfolio, we do not expect the transition impact of adopting the new guidance will be material to EnPro. Many of the affected service contracts mentioned above are over relatively short periods of time and not for large amounts of consideration, and we currently have only a single engine contract that we have determined to have multiple performance obligations that are distinct within the context of the contract.

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition	The following table presents the purchase price allocation for acquisitions made in 2017: (in millions) Accounts receivable $ 1.6 Inventories 3.4 Property, plant and equipment 3.2 Goodwill 9.8 Other intangible assets 27.7 Other assets 0.2 Liabilities assumed (1.3 ) Total purchase price $ 44.6

Other Expense (Tables)

Other Expense (Tables)	12 Months Ended
	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Schedule of Restructuring Reserves	Restructuring reserves at December 31, 2017 , as well as activity during the year, consisted of: Balance Provision Payments Balance (in millions) Personnel-related costs $ 3.5 $ 2.5 $ (5.3 ) $ 0.7 Facility relocation and closure costs 1.6 0.6 (1.0 ) 1.2 $ 5.1 $ 3.1 $ (6.3 ) $ 1.9 Also included in restructuring costs for 2017 were asset write-downs of approximately $2.0 million that did not affect the restructuring reserve liability. Restructuring reserves at December 31, 2016 , as well as activity during the year, consisted of: Balance Provision Payments Balance (in millions) Personnel-related costs $ 0.3 $ 8.3 $ (5.1 ) $ 3.5 Facility relocation and closure costs — 4.3 (2.7 ) 1.6 $ 0.3 $ 12.6 $ (7.8 ) $ 5.1 Also included in restructuring costs for 2016 were asset write-downs of approximately $0.8 million that did not affect the restructuring reserve liability. Restructuring reserves at December 31, 2015 , as well as activity during the year, consisted of: Balance, December 31, 2014 Provision Payments Balance (in millions) Personnel-related costs $ 1.1 $ 3.0 $ (3.8 ) $ 0.3 Facility relocation and closure costs 0.7 0.9 (1.6 ) — $ 1.8 $ 3.9 $ (5.4 ) $ 0.3
Schedule of Restructuring Costs By Reportable Segment	Restructuring costs by reportable segment are as follows: Years Ended December 31, 2017 2016 2015 (in millions) Sealing Products $ 3.6 $ 3.3 $ 0.4 Engineered Products 1.5 6.8 6.2 Power Systems — 0.4 — Corporate — 2.9 — $ 5.1 $ 13.4 $ 6.6

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Schedule of Income Before Income Tax Domestic and Foreign	Income (loss) before income taxes as shown in the Consolidated Statements of Operations consists of the following: Years Ended December 31, 2017 2016 2015 (in millions) Domestic $ 524.1 $ (96.4 ) $ (3.0 ) Foreign 53.4 27.7 (15.6 ) Total $ 577.5 $ (68.7 ) $ (18.6 )
Summary of Income Tax Expense in Consolidated Statements of Operations From Continuing Operations	A summary of income tax benefit (expense) in the Consolidated Statements of Operations is as follows: Years Ended December 31, 2017 2016 2015 (in millions) Current: Federal $ (15.6 ) $ (8.7 ) $ (4.0 ) Foreign 17.6 10.6 9.8 State (0.2 ) (0.5 ) (2.4 ) 1.8 1.4 3.4 Deferred: Federal 14.4 (25.5 ) 3.6 Foreign 17.0 0.2 (6.0 ) State 4.5 (4.7 ) 1.3 35.9 (30.0 ) (1.1 ) Total $ 37.7 $ (28.6 ) $ 2.3
Schedule of Income Tax Benefits Recorded in Additional Paid-in-Capital	Income tax benefits recorded directly to additional paid-in capital consisted of the following: Years Ended December 31, 2017 2016 2015 (in millions) Stock options exercised and restricted stock units vested $ — $ — $ (1.8 ) $ — $ — $ (1.8 )
Schedule of Deferred Income Tax Assets and Liabilities	The net deferred tax assets are reflected on the December 31, 2017 and 2016 Consolidated Balance Sheets as follows: 2017 2016 (in millions) Deferred income taxes and income tax receivable $ 24.8 $ 33.6 Other liabilities (non-current) (18.1 ) (4.2 ) Net deferred tax assets $ 6.7 $ 29.4 Significant components of deferred income tax assets and liabilities at December 31, 2017 and 2016 are as follows: 2017 2016 (in millions) Deferred income tax assets: Net operating losses and tax credits $ 89.6 $ 13.8 Accrual for post-retirement benefits other than pensions 4.1 4.5 Environmental reserves 6.5 8.7 Retained liabilities of previously owned businesses 1.2 2.1 Accruals and reserves 6.2 8.7 Pension obligations — 10.2 Inventories 2.5 5.1 Asbestos settlement — 41.4 Interest 12.0 9.9 Compensation and benefits 5.2 10.8 Gross deferred income tax assets 127.3 115.2 Valuation allowance (25.7 ) (20.2 ) Total deferred income tax assets 101.6 95.0 Deferred income tax liabilities: Depreciation and amortization (86.6 ) (44.2 ) GST deconsolidation gain — (21.4 ) Joint ventures and partnerships (0.3 ) — Asbestos settlement (6.3 ) — Pension obligations (1.7 ) — Total deferred income tax liabilities (94.9 ) (65.6 ) Net deferred tax assets $ 6.7 $ 29.4
Reconciliation of Effective Tax Rate	The effective income tax rate from operations varied from the statutory federal income tax rate as follows: Percent of Pretax Income Years Ended December 31, 2017 2016 2015 Statutory federal income tax rate 35.0 % 35.0 % 35.0 % U.S. taxation of foreign profits, net of foreign tax credits 0.1 1.1 1.1 Research and employment tax credits (0.4 ) 3.2 7.7 State and local taxes 0.2 4.9 4.1 Domestic production activities (0.4 ) 1.8 5.5 Nondeductible goodwill impairment — — (48.6 ) Foreign tax rate differences (1.0 ) 4.3 (10.2 ) Uncertain tax positions (0.1 ) (1.4 ) 4.3 Statutory changes in tax rates 0.3 0.2 1.4 Valuation allowance 0.2 (6.7 ) (2.1 ) Nondeductible expenses 0.3 (1.1 ) (6.6 ) Gain on reconsolidation of GST and OldCo (32.4 ) — — Reconsolidation step-up of net assets of GST and OldCo to fair value 9.0 — — Tax Act (5.3 ) — — Other items, net 1.0 0.4 (3.9 ) Effective income tax rate 6.5 % 41.7 % (12.3 )%
Schedule of Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of the gross unrecognized tax benefits (excluding interest) is as follows: (in millions) 2017 2016 2015 Balance at beginning of year $ 2.8 $ 1.5 $ 3.1 Reconsolidation of GST and OldCo 0.2 — — Additions based on tax positions related to the current year 0.3 0.4 0.3 Additions for tax positions of prior years 1.1 1.1 0.2 Reductions as a result of a lapse in the statute of limitations (0.3 ) (0.2 ) (2.0 ) Reductions as a result of audit settlements (0.3 ) — — Changes due to fluctuations in foreign currency — — (0.1 ) Balance at end of year $ 3.8 $ 2.8 $ 1.5

Earnings (Loss) Per Share (Tabl

Earnings (Loss) Per Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Schedule of Computation of Basic and Diluted Earnings Per Share	The computation of basic and diluted earnings per share is as follows (in millions, except per share data): 2017 2016 2015 Numerator (basic and diluted): Net income (loss) $ 539.8 $ (40.1 ) $ (20.9 ) Denominator: Weighted-average shares – basic 21.3 21.6 22.5 Share-based awards 0.5 — — Weighted-average shares – diluted 21.8 21.6 22.5 Earnings (loss) per share: Basic $ 25.28 $ (1.86 ) $ (0.93 ) Diluted $ 24.76 $ (1.86 ) $ (0.93 )

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2017
Inventory Disclosure [Abstract]
Schedule of Inventories	As of December 31, 2017 2016 (in millions) Finished products $ 121.4 $ 108.1 Work in process 33.0 23.7 Raw materials and supplies 59.2 49.3 213.6 181.1 Reserve to reduce certain inventories to LIFO basis (10.2 ) (12.1 ) Manufacturing inventories 203.4 169.0 Incurred costs related to long-term contracts 0.7 13.6 Progress payments related to long-term contracts — (7.2 ) Net balance associated with completed-contract inventories 0.7 6.4 Total inventories $ 204.1 $ 175.4

Long-Term Contracts Long-Term C

Long-Term Contracts Long-Term Contracts - Percentage-of-Completion Long-Term Contracts (Tables)	12 Months Ended
	Dec. 31, 2017
Contractors [Abstract]
Schedule of Information Regarding Contracts Accounted for Under the Percentage-of-Completion Method	Additional information regarding engine contracts accounted for under the POC method is as follows: As of December 31, 2017 2016 (in millions) Cumulative revenues recognized on uncompleted POC contracts $ 348.2 $ 260.7 Cumulative billings on uncompleted POC contracts 300.7 231.6 $ 47.5 $ 29.1
Schedule of Uncompleted Contracts Reflected in Consolidated Balance Sheets	These amounts were included in the accompanying Consolidated Balance Sheets under the following captions: As of December 31, 2017 2016 (in millions) Accounts receivable (POC revenue recognized in excess of billings) $ 51.7 $ 31.4 Accrued expenses (billings in excess of POC revenue recognized) (4.2 ) (2.3 ) $ 47.5 $ 29.1
Schedule of Completed-Contract Method Contracts	Additional information regarding engine contracts accounted for under the completed-contract method is as follows: As of December 31, 2017 2016 (in millions) Incurred costs relating to long-term contracts $ — $ 0.1 Progress payments related to long-term contracts — (1.0 ) Net balance associated with completed-contract inventories $ — $ (0.9 )

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Schedule of Property Plant and Equipment	As of December 31, 2017 2016 (in millions) Land $ 13.9 $ 11.0 Buildings and improvements 141.5 112.8 Machinery and equipment 448.7 367.8 Construction in progress 31.9 31.2 636.0 522.8 Less accumulated depreciation (339.1 ) (307.4 ) Total $ 296.9 $ 215.4

Goodwill and Other Intangible40

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Changes in Net Carrying Value of Goodwill by Reportable Segment	The changes in the net carrying value of goodwill by reportable segment for the years ended December 31, 2017 and 2016 are as follows: Sealing Products Engineered Products Power Systems Total (in millions) Goodwill as of December 31, 2015 $ 179.7 $ 9.1 $ 7.1 $ 195.9 Foreign currency translation (1.5 ) — — (1.5 ) Sale of businesses (0.7 ) — — (0.7 ) Acquisitions 7.8 — — 7.8 Goodwill as of December 31, 2016 185.3 9.1 7.1 201.5 Foreign currency translation (0.7 ) — — (0.7 ) Acquisitions 9.8 — — 9.8 Reconsolidation of GST and OldCo 118.8 1.8 4.9 125.5 Goodwill as of December 31, 2017 $ 313.2 $ 10.9 $ 12.0 $ 336.1
Schedule of Identifiable Intangible Assets	Identifiable intangible assets are as follows: As of December 31, 2017 As of December 31, 2016 Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated Amortization (in millions) Amortized: Customer relationships $ 311.2 $ 138.0 $ 216.2 $ 122.0 Existing technology 113.0 37.5 63.0 31.0 Trademarks 35.8 22.3 35.4 19.6 Other 28.7 23.2 23.2 22.1 488.7 221.0 337.8 194.7 Indefinite-Lived: Trademarks 79.3 — 33.8 — Total $ 568.0 $ 221.0 $ 371.6 $ 194.7
Schedule of Estimated Amortization Expense of Intangible Assets	The estimated amortization expense for those intangible assets for the next five years is as follows (in millions): 2018 $ 29.8 2019 $ 29.1 2020 $ 28.7 2021 $ 26.3 2022 $ 20.9

Accrued Expenses (Tables)

Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2017
Payables and Accruals [Abstract]
Schedule of Accrued Expenses	As of December 31, 2017 2016 (in millions) Salaries, wages and employee benefits $ 63.7 $ 40.0 Interest 8.6 38.1 Customer advances 7.1 5.3 Income and other taxes 14.3 11.2 Other 42.9 36.4 $ 136.6 $ 131.0

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2017
Related Party Transactions [Abstract]
Schedule of Amounts Included in Financial Statements Arising From Transactions with GST	Consolidated Statements of Operations Caption Seven Months Ended July 30, 2017 Years Ended December 31, Description 2016 2015 (in millions) Sales to GST Net sales $ 20.8 $ 28.0 $ 30.6 Purchases from GST Cost of sales $ 12.2 $ 17.7 $ 20.7 Interest expense to GST Interest expense $ 20.6 $ 33.5 $ 31.6 Consolidated Balance Sheets Caption December 31, 2016 Description (in millions) Due from GST Accounts receivable, net $ 21.4 Income tax receivable from GST Deferred income taxes and income tax receivable $ 119.0 Due from GST Other assets $ 1.4 Due to GST Accounts payable $ 6.3 Accrued interest to GST Accrued expenses $ 32.6

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Schedule of Long Term Debt	As of December 31, 2017 2016 (in millions) Senior Notes 444.2 294.1 Revolving debt 173.5 130.0 Other notes payable 0.8 0.9 618.5 425.0 Less current maturities of long-term debt 0.2 0.2 $ 618.3 $ 424.8
Schedule of Future Principal Payments on Long Term Debt	Future principal payments on long-term debt are as follows: (in millions) 2018 $ 0.2 2019 173.7 2020 0.2 2021 0.1 2022 450.0 Thereafter 0.1 $ 624.3

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on Recurring Basis	Assets and liabilities measured at fair value on a recurring basis are summarized as follows: Fair Value Measurements as of December 31, 2017 December 31, 2016 (in millions) Assets Time deposits $ — $ 26.0 Deferred compensation assets 7.8 7.0 $ 7.8 $ 33.0 Liabilities Deferred compensation liabilities $ 8.9 $ 8.3
Schedule of Carrying Value of Financial Instruments	The carrying values of our significant financial instruments reflected in the Consolidated Balance Sheets approximate their respective fair values, except for the following: December 31, 2017 December 31, 2016 Carrying Value Fair Value Carrying Value Fair Value (in millions) Long-term debt $ 618.5 $ 645.6 $ 425.0 $ 439.1 Notes payable to GST $ — $ — $ 295.9 $ 302.7

Pensions and Postretirement B45

Pensions and Postretirement Benefits (Tables)	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
Schedule of Change in Projected Benefit Obligations	The following table sets forth the changes in projected benefit obligations and plan assets of our defined benefit pension and other non-qualified and postretirement plans as of and for the years ended December 31, 2017 and 2016 . Pension Benefits Other Benefits 2017 2016 2017 2016 (in millions) Change in Projected Benefit Obligations Projected benefit obligations at beginning of year $ 289.7 $ 283.4 $ 3.2 $ 3.4 Service cost 4.5 4.3 0.1 0.1 Interest cost 12.9 12.7 0.1 0.2 Actuarial loss (gain) 16.1 8.9 — (0.3 ) Amendments 0.2 — — — Benefits paid (13.6 ) (18.1 ) (0.9 ) (0.2 ) Reconsolidation of GST and OldCo 58.8 — 2.1 — Other 0.6 (1.5 ) 0.1 — Projected benefit obligations at end of year 369.2 289.7 4.7 3.2
Schedule of Change in Plan Assets	Change in Plan Assets Fair value of plan assets at beginning of year 256.9 242.5 Actual return on plan assets 42.3 17.3 Administrative expenses (0.8 ) (0.4 ) Benefits paid (13.6 ) (18.1 ) Company contributions 9.4 15.6 Reconsolidation of GST and OldCo 56.5 — Fair value of plan assets at end of year 350.7 256.9
Schedule of Change in Plan Assets Underfunded Status at End of Year	Underfunded Status at End of Year $ (18.5 ) $ (32.8 ) $ (4.7 ) $ (3.2 )
Schedule Of Projected Benefit Obligations Amounts Recognized In Consolidated Balance Sheets	Amounts Recognized in the Consolidated Balance Sheets Long-term assets $ 0.8 $ — $ — $ — Current liabilities (0.5 ) (0.4 ) (0.3 ) (0.1 ) Long-term liabilities (18.8 ) (32.4 ) (4.4 ) (3.1 ) $ (18.5 ) $ (32.8 ) $ (4.7 ) $ (3.2 )
Schedule of Pre Tax Charges Recognized in Accumulated Other Comprehensive Income (Loss)	Pre-tax charges recognized in accumulated other comprehensive loss as of December 31, 2017 and 2016 consist of: Pension Benefits Other Benefits 2017 2016 2017 2016 (in millions) Net actuarial (gain) loss $ 65.3 $ 78.4 $ (0.3 ) $ (0.4 ) Prior service cost 1.4 1.2 0.3 0.4 $ 66.7 $ 79.6 $ — $ —
Schedule Of Net Periodic Benefit Cost	Pension Benefits Other Benefits 2017 2016 2015 2017 2016 2015 (in millions) Net Periodic Benefit Cost Service cost $ 4.5 $ 4.3 $ 4.9 $ 0.1 $ 0.1 $ 0.1 Interest cost 12.9 12.7 12.0 0.1 0.2 0.2 Expected return on plan assets (20.1 ) (17.2 ) (18.2 ) — — — Amortization of prior service cost 0.3 0.2 0.2 0.1 0.1 — Amortization of net loss 7.3 6.9 6.9 — — — Curtailment (0.1 ) (0.1 ) — — (0.3 ) — Deconsolidation of GST (0.3 ) (0.9 ) (0.7 ) — — — Net periodic benefit cost 4.5 5.9 5.1 0.3 0.1 0.3
Schedule of Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income	Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income Net loss (gain) (5.8 ) 8.2 3.3 0.1 (0.4 ) (0.4 ) Prior service cost 0.5 — — — — 0.6 Amortization of net loss (7.3 ) (6.9 ) (6.9 ) — — — Amortization of prior service cost (0.3 ) (0.2 ) (0.2 ) (0.1 ) (0.1 ) — Other adjustment — — (0.1 ) — 0.3 — Total recognized in other comprehensive income (12.9 ) 1.1 (3.9 ) — (0.2 ) 0.2 Total Recognized in Net Periodic Benefit Cost and Other Comprehensive Income $ (8.4 ) $ 7.0 $ 1.2 $ 0.3 $ (0.1 ) $ 0.5
Schedule of Weighted Average Assumptions Used to Determine Benefit Obligations and Net Periodic Benefit Cost	Pension Benefits Other Benefits 2017 2016 2015 2017 2016 2015 Weighted-Average Assumptions Used to Determine Benefit Obligations at December 31 Discount rate 3.75 % 4.25 % 4.63 % 3.75 % 4.25 % 4.63 % Rate of compensation increase 3.0 % 3.0 % 3.0 % 4.0 % 4.0 % 4.0 % Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost for Years Ended December 31 Discount rate 4.25 % 4.63 % 4.25 % 4.25 % 4.63 % 4.25 % Expected long-term return on plan assets 7.25 % 7.25 % 7.25 % — — — Rate of compensation increase 3.0 % 3.0 % 3.0 % 4.0 % 4.0 % 4.0 %
Schedule of Assumed Health Care Cost Trend Rates	We use the RP-2014 mortality table with the MP-2017 projection scale to value our domestic pension liabilities. Assumed Health Care Cost Trend Rates at December 31 2017 2016 Health care cost trend rate assumed for next year 8.0 % 8.0 % Rate to which the cost trend rate is assumed to decline (the ultimate rate) 4.5 % 4.5 % Year that the rate reaches the ultimate trend rate 2025 2024
Schedule of Asset Allocation for Pension Plans and Target Allocation By Asset Category	The asset allocation for pension plans at the end of 2017 and 2016 , and the target allocation for 2018 , by asset category are as follows: Target Allocation Plan Assets at December 31, 2018 2017 2016 Asset Category Equity securities 30 % 30 % 40 % Fixed income 70 % 70 % 60 % 100 % 100 % 100 %
Schedule of Fair Value of Plan Assets	The investment portfolios of the various funds at December 31, 2017 and 2016 are summarized as follows: 2017 2016 (in millions) Mutual funds – U.S. equity $ 61.6 $ 65.7 Mutual funds - fixed income treasury and money market 244.6 153.3 Mutual funds – international equity 43.3 37.0 Cash equivalents 1.2 0.9 $ 350.7 $ 256.9
Schedule of Benefit Payments Reflecting Expected Future Service as Appropriate Expected to Be Paid	The following benefit payments, which reflect expected future service, as appropriate, are expected to be paid: Pension Benefits Other Benefits (in millions) 2018 $ 16.4 $ 0.5 2019 17.1 0.5 2020 18.0 1.5 2021 18.8 0.5 2022 19.6 0.4 Years 2023 – 2027 111.2 1.5

Accumulated Other Comprehensi46

Accumulated Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	Changes in accumulated other comprehensive loss by component (after tax) are as follows: (in millions) Unrealized Translation Adjustments Pension and Other Postretirement Plans Total Balance at December 31, 2014 $ 17.0 $ (51.1 ) $ (34.1 ) Other comprehensive loss before reclassifications (21.9 ) (1.8 ) (23.7 ) Amounts reclassified from accumulated other comprehensive income (loss) — 3.7 3.7 Net current-period other comprehensive loss (21.9 ) 1.9 (20.0 ) Balance at December 31, 2015 (4.9 ) (49.2 ) (54.1 ) Other comprehensive loss before reclassifications (16.1 ) (5.0 ) (21.1 ) Amounts reclassified from accumulated other comprehensive loss (0.2 ) 4.5 4.3 Net current-period other comprehensive loss (16.3 ) (0.5 ) (16.8 ) Balance at December 31, 2016 (21.2 ) (49.7 ) (70.9 ) Other comprehensive income before reclassifications 14.4 3.2 17.6 Amounts reclassified from accumulated other comprehensive loss — 4.9 4.9 Net current-period other comprehensive income 14.4 8.1 22.5 Balance at December 31, 2017 $ (6.8 ) $ (41.6 ) $ (48.4 )
Components Of Accumulated Other Comprehensive Income Loss	Reclassifications out of accumulated other comprehensive loss are as follows: Details about Accumulated Other Comprehensive Loss Components Amount Reclassified from Accumulated Other Comprehensive Loss Affected Statement of Operations Caption Years Ended December 31, 2017 2016 2015 (in millions) Amortization of pension and other postretirement plans: Actuarial losses $ 7.3 $ 6.6 $ 6.9 (1) Prior service costs 0.4 0.3 0.2 (1) Total before tax 7.7 6.9 7.1 Tax benefit (2.8 ) (2.4 ) (3.4 ) Income tax expense Net of tax $ 4.9 $ 4.5 $ 3.7 Release of unrealized currency translation adjustment upon sale of investment in foreign entity, net of tax $ — $ (0.2 ) $ — Other non-operating expense (1) These accumulated other comprehensive income (loss) components are included in the computation of net periodic pension cost. (See Note 15, "Pensions and Postretirement Benefits" for additional details).

Equity Compensation Plan (Table

Equity Compensation Plan (Tables)	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Information With Respect to Stock Options	We used the following assumptions in determining the fair value of these awards: Expected stock price volatility Annual expected dividend yield Risk free interest ate Correlation between Total Shareholder Return for EnPro and the applicable S&P index Shares granted February 13, 2017 EnPro Industries, Inc. 31.23 % 1.23 % 1.45 % 0.6259 S&P 600 Capital Goods Index 34.86 % n/a 1.45 % Shares granted February 23, 2016 EnPro Industries, Inc. 27.36 % 1.82 % 0.88 % 0.5895 S&P 600 Capital Goods Index 32.80 % n/a 0.88 %
Summary of Restricted Share Units Activity, Performance Share Activity and Restricted Stock Activity	A summary of award activity under these plans is as follows: Restricted Share Units Performance Shares Restricted Stock Shares Weighted- Average Grant Date Fair Value Shares Weighted- Average Grant Date Fair Value Shares Weighted- Average Grant Date Fair Value Nonvested at December 31, 2014 269,585 $ 54.60 227,220 $ 55.65 11,330 $ 55.09 Granted 94,623 63.98 115,197 68.31 — — Vested (38,457 ) 37.67 (98,230 ) 44.63 — — Forfeited (34,157 ) 59.34 (3,398 ) 60.09 — — Achievement level adjustment — — (42,387 ) 44.63 — — Shares settled for cash (27,563 ) 37.65 — — — — Nonvested at December 31, 2015 264,031 61.74 198,402 67.22 11,330 55.09 Granted 111,320 44.29 199,965 49.68 — — Vested (59,104 ) 45.20 — — (11,330 ) 55.09 Forfeited (42,090 ) 58.48 (37,542 ) 54.66 — — Achievement level adjustment — — (77,310 ) 71.83 — — Shares settled for cash (12,135 ) 44.63 — — — — Nonvested at December 31, 2016 262,022 59.43 283,515 54.84 — — Granted 77,120 68.55 84,534 76.93 — — Vested (79,417 ) 64.16 (76,487 ) 63.81 — — Forfeited (17,607 ) 56.32 (8,823 ) 61.43 — — Achievement level adjustment — — (12,140 ) 63.81 — — Shares settled for cash (6,561 ) 54.29 — — — — Nonvested at December 31, 2017 235,557 $ 57.87 270,599 $ 61.92 — $ —
Summary of Option Activity Under Plan	A summary of option activity under the Plan as of December 31, 2017 , and changes during the year then ended, is presented below: Share Options Outstanding Weighted Average Exercise Price Balance at December 31, 2016 79,505 $ 36.31 Exercised (61,318 ) 34.55 Balance at December 31, 2017 18,187 $ 42.24 The outstanding options are all exercisable, with an exercise price of $42.24 and a remaining contractual life of 3.12 years.
Schedule Of Intrinsic Value Related to stock Options	The year-end intrinsic value related to stock options is presented below: As of and for the Years Ended December 31, (in millions) 2017 2016 2015 Options outstanding $ 0.9 $ 2.5 $ 0.9 Options exercisable $ 0.9 $ 2.5 $ 0.9 Options exercised $ 2.2 $ 0.7 $ 0.1
Schedule of Equity Based Compensation	We recognized the following equity-based employee compensation expenses and benefits related to our Plan activity: Years Ended December 31, (in millions) 2017 2016 2015 Compensation expense $ 9.5 $ 5.1 $ 4.1 Related income tax benefit $ 3.6 $ 1.9 $ 1.5

Business Segment Information (T

Business Segment Information (Tables)	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Schedule of Segment Operating Results and Other Financial Data	Segment operating results and other financial data for the years ended December 31, 2017 , 2016 , and 2015 were as follows: Years Ended December 31, 2017 2016 2015 (in millions) Sales Sealing Products $ 804.3 $ 705.6 $ 705.6 Engineered Products 301.1 277.1 297.8 Power Systems 208.2 208.3 204.6 1,313.6 1,191.0 1,208.0 Intersegment sales (4.0 ) (3.3 ) (3.6 ) Total sales $ 1,309.6 $ 1,187.7 $ 1,204.4 Segment Profit Sealing Products $ 90.9 $ 81.8 $ 84.3 Engineered Products 29.8 12.4 6.4 Power Systems 29.0 17.0 27.1 Total segment profit 149.7 111.2 117.8 Corporate expenses (34.3 ) (30.0 ) (28.2 ) Goodwill and other intangible asset impairment (10.1 ) — (47.0 ) Asbestos settlement — (80.0 ) — Interest expense, net (49.4 ) (55.1 ) (52.1 ) Gain on reconsolidation of GST and OldCo 534.4 — — Other expense, net (12.8 ) (14.8 ) (9.1 ) Income (loss) before income taxes $ 577.5 $ (68.7 ) $ (18.6 ) No customer accounted for 10% or more of net sales in 2017 , 2016 or 2015 .
Schedule of Segment Related Capital Expenditure, Depreciation and Amortization on those Expenditures	Years Ended December 31, 2017 2016 2015 (in millions) Capital Expenditures Sealing Products $ 20.4 $ 22.9 $ 17.0 Engineered Products 9.9 7.2 14.8 Power Systems 10.7 5.7 4.9 Corporate — — 0.1 Total capital expenditures $ 41.0 $ 35.8 $ 36.8 Depreciation and Amortization Expense Sealing Products $ 41.8 $ 35.1 $ 34.3 Engineered Products 16.8 17.5 19.4 Power Systems 5.2 4.4 4.1 Corporate — 0.1 0.3 Total depreciation and amortization $ 63.8 $ 57.1 $ 58.1
Schedule of Net Sales by Geographical Area	Net Sales by Geographic Area United States $ 750.6 $ 682.4 $ 696.2 Europe 292.6 289.9 289.5 Other foreign 266.4 215.4 218.7 Total $ 1,309.6 $ 1,187.7 $ 1,204.4
Schedule of Total Assets Segment	As of December 31, 2017 2016 (in millions) Assets Sealing Products $ 1,078.0 $ 636.4 Engineered Products 229.2 210.0 Power Systems 210.8 164.8 Corporate 368.1 535.2 $ 1,886.1 $ 1,546.4
Schedule of Long Lived Assets Segment	Long-Lived Assets United States $ 206.9 $ 148.6 France 26.5 23.0 Other Europe 23.4 20.7 Other foreign 40.1 23.1 Total $ 296.9 $ 215.4

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Schedule Of Changes In Carrying Amount Of Product Warranty Liability	Changes in the carrying amount of the product warranty liability for the years ended December 31, 2017 , 2016 and 2015 are as follows: 2017 2016 2015 (in millions) Balance at beginning of year $ 5.0 $ 4.8 $ 3.5 Charges to expense 2.6 4.4 3.3 Settlements made (2.3 ) (4.2 ) (2.0 ) Balance at end of year $ 5.3 $ 5.0 $ 4.8
Schedule Of Future Minimum Lease Payments	Future minimum lease payments by year and in the aggregate, under noncancelable operating leases with initial or remaining noncancelable lease terms in excess of one year, consisted of the following at December 31, 2017 (in millions): 2018 $ 12.3 2019 10.6 2020 9.0 2021 6.8 2022 5.3 Thereafter 5.4 Total minimum payments $ 49.4

Supplemental Guarantor Financ50

Supplemental Guarantor Financial Information (Tables)	12 Months Ended
	Dec. 31, 2017
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Income Statement	ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS Year Ended December 31, 2015 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated Net sales $ — $ 837.8 $ 428.1 $ (61.5 ) $ 1,204.4 Cost of sales — 591.6 278.8 (61.5 ) 808.9 Gross profit — 246.2 149.3 — 395.5 Operating expenses: Selling, general and administrative 27.6 157.1 118.1 — 302.8 Goodwill and other intangible asset impairment — 5.6 41.4 — 47.0 Other 1.8 1.2 5.1 — 8.1 Total operating expenses 29.4 163.9 164.6 — 357.9 Operating income (loss) (29.4 ) 82.3 (15.3 ) — 37.6 Interest income (expense), net (13.1 ) (38.8 ) (0.2 ) — (52.1 ) Other expense, net (2.8 ) (1.3 ) — — (4.1 ) Income (loss) before income taxes (45.3 ) 42.2 (15.5 ) — (18.6 ) Income tax benefit (expense) 12.1 (9.5 ) (4.9 ) — (2.3 ) Income (loss) before equity in earnings of subsidiaries (33.2 ) 32.7 (20.4 ) — (20.9 ) Equity in earnings of subsidiaries, net of tax 12.3 (20.4 ) — 8.1 — Net income (loss) $ (20.9 ) $ 12.3 $ (20.4 ) $ 8.1 $ (20.9 ) ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS Year Ended December 31, 2017 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated Net sales $ — $ 921.9 $ 497.3 $ (109.6 ) $ 1,309.6 Cost of sales — 644.6 330.2 (109.6 ) 865.2 Gross profit — 277.3 167.1 — 444.4 Operating expenses: Selling, general and administrative 33.1 183.0 110.2 — 326.3 Other 1.1 12.1 3.7 — 16.9 Total operating expenses 34.2 195.1 113.9 — 343.2 Operating income (loss) (34.2 ) 82.2 53.2 — 101.2 Interest income (expense), net (25.4 ) (24.1 ) 0.1 — (49.4 ) Gain on reconsolidation of GST and OldCo — 534.4 — — 534.4 Other expense, net — (8.7 ) — — (8.7 ) Income (loss) before income taxes (59.6 ) 583.8 53.3 — 577.5 Income tax benefit (expense) 17.6 (20.7 ) (34.6 ) — (37.7 ) Income (loss) before equity in earnings of subsidiaries (42.0 ) 563.1 18.7 — 539.8 Equity in earnings of subsidiaries, net of tax 581.8 18.7 — (600.5 ) — Net income $ 539.8 $ 581.8 $ 18.7 $ (600.5 ) $ 539.8 ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS Year Ended December 31, 2016 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated Net sales $ — $ 829.0 $ 439.7 $ (81.0 ) $ 1,187.7 Cost of sales — 582.4 291.6 (81.0 ) 793.0 Gross profit — 246.6 148.1 — 394.7 Operating expenses: Selling, general and administrative 27.7 164.0 112.1 — 303.8 Asbestos settlement — 80.0 — — 80.0 Other 4.8 3.3 7.5 — 15.6 Total operating expenses 32.5 247.3 119.6 — 399.4 Operating income (loss) (32.5 ) (0.7 ) 28.5 — (4.7 ) Interest expense, net (18.5 ) (36.2 ) (0.4 ) — (55.1 ) Other expense, net — (8.4 ) (0.5 ) — (8.9 ) Income (loss) before income taxes (51.0 ) (45.3 ) 27.6 — (68.7 ) Income tax benefit (expense) 17.6 21.7 (10.7 ) — 28.6 Income (loss) before equity in earnings of subsidiaries (33.4 ) (23.6 ) 16.9 — (40.1 ) Equity in earnings of subsidiaries, net of tax (6.7 ) 16.9 — (10.2 ) — Net income (loss) $ (40.1 ) $ (6.7 ) $ 16.9 $ (10.2 ) $ (40.1 )
Condensed Statement of Comprehensive Income	ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME Year Ended December 31, 2015 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated Net income $ (20.9 ) $ 12.3 $ (20.4 ) $ 8.1 $ (20.9 ) Other comprehensive income (loss): Foreign currency translation adjustments (21.9 ) (21.9 ) (21.9 ) 43.8 (21.9 ) Pension and post-retirement benefits adjustment (excluding amortization) (3.4 ) (3.6 ) 0.5 3.1 (3.4 ) Amortization of pension and post-retirement benefits included in net income 7.1 7.1 0.2 (7.3 ) 7.1 Other comprehensive loss, before tax (18.2 ) (18.4 ) (21.2 ) 39.6 (18.2 ) Income tax benefit related to items of other comprehensive loss (1.8 ) (1.7 ) (0.2 ) 1.9 (1.8 ) Other comprehensive loss, net of tax (20.0 ) (20.1 ) (21.4 ) 41.5 (20.0 ) Comprehensive loss $ (40.9 ) $ (7.8 ) $ (41.8 ) $ 49.6 $ (40.9 ) ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME Year Ended December 31, 2017 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated Net income $ 539.8 $ 581.8 $ 18.7 $ (600.5 ) $ 539.8 Other comprehensive income: Foreign currency translation adjustments 14.4 14.4 14.4 (28.8 ) 14.4 Pension and post-retirement benefits adjustment (excluding amortization) 5.2 5.2 1.3 (6.5 ) 5.2 Amortization of pension and post-retirement benefits included in net income 7.7 7.7 0.1 (7.8 ) 7.7 Other comprehensive income, before tax 27.3 27.3 15.8 (43.1 ) 27.3 Income tax expense related to items of other comprehensive income (4.8 ) (4.8 ) (0.4 ) 5.2 (4.8 ) Other comprehensive income, net of tax 22.5 22.5 15.4 (37.9 ) 22.5 Comprehensive income $ 562.3 $ 604.3 $ 34.1 $ (638.4 ) $ 562.3 ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME Year Ended December 31, 2016 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated Net income (loss) $ (40.1 ) $ (6.7 ) $ 16.9 $ (10.2 ) $ (40.1 ) Other comprehensive income (loss): Foreign currency translation adjustments (16.3 ) (16.3 ) (16.3 ) 32.6 (16.3 ) Pension and post-retirement benefits adjustment (excluding amortization) (7.8 ) (8.3 ) 0.6 7.7 (7.8 ) Amortization of pension and post-retirement benefits included in net income (loss) 6.9 6.6 0.2 (6.8 ) 6.9 Other comprehensive loss, before tax (17.2 ) (18.0 ) (15.5 ) 33.5 (17.2 ) Income tax expense related to items of other comprehensive income (loss) 0.4 0.5 (0.2 ) (0.3 ) 0.4 Other comprehensive loss, net of tax (16.8 ) (17.5 ) (15.7 ) 33.2 (16.8 ) Comprehensive income (loss) $ (56.9 ) $ (24.2 ) $ 1.2 $ 23.0 $ (56.9 )
Condensed Cash Flow Statement	ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS Year Ended December 31, 2017 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES $ (106.5 ) $ 61.9 $ 91.3 $ (0.1 ) $ 46.6 INVESTING ACTIVITIES Purchases of property, plant and equipment — (28.2 ) (12.8 ) — (41.0 ) Payments for capitalized internal-use software — (3.6 ) (0.1 ) — (3.7 ) Payments for acquisitions — (39.5 ) (5.1 ) — (44.6 ) Reconsolidation of GST and OldCo — 41.1 — — 41.1 Deconsolidation of OldCo — (4.8 ) — — (4.8 ) Capital contribution to OldCo — (45.2 ) — — (45.2 ) Other — — 0.5 — 0.5 Net cash used in investing activities — (80.2 ) (17.5 ) — (97.7 ) FINANCING ACTIVITIES Net payments between subsidiaries (12.1 ) 19.3 (7.2 ) — — Intercompany dividends — — (0.1 ) 0.1 — Proceeds from debt 151.5 480.7 3.5 — 635.7 Repayments of debt — (482.5 ) (1.8 ) — (484.3 ) Repurchase of common stock (11.5 ) — — — (11.5 ) Dividends paid (19.0 ) — — — (19.0 ) Other (2.4 ) — — — (2.4 ) Net cash provided by (used in) financing activities 106.5 17.5 (5.6 ) 0.1 118.5 Effect of exchange rate changes on cash and cash equivalents — — 10.4 — 10.4 Net increase (decrease) in cash and cash equivalents — (0.8 ) 78.6 — 77.8 Cash and cash equivalents at beginning of year — 0.8 110.7 — 111.5 Cash and cash equivalents at end of year $ — $ — $ 189.3 $ — $ 189.3 ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS Year Ended December 31, 2016 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES $ (45.9 ) $ 82.9 $ 39.7 $ (12.2 ) $ 64.5 INVESTING ACTIVITIES Purchases of property, plant and equipment — (28.4 ) (7.4 ) — (35.8 ) Payments for capitalized internal-use software — (3.8 ) (0.3 ) — (4.1 ) Proceeds from sale of business — 2.9 3.7 — 6.6 Payments for acquisitions — (25.5 ) (3.0 ) — (28.5 ) Other — — 0.4 — 0.4 Net cash used in investing activities — (54.8 ) (6.6 ) — (61.4 ) FINANCING ACTIVITIES Net payments between subsidiaries 96.6 (95.6 ) (1.0 ) — — Intercompany dividends — — (12.2 ) 12.2 — Proceeds from debt — 344.7 6.1 — 350.8 Repayments of debt — (277.1 ) (1.0 ) — (278.1 ) Repurchase of common stock (30.4 ) — — — (30.4 ) Dividends paid (18.1 ) — — — (18.1 ) Other (2.2 ) — — — (2.2 ) Net cash provided by (used in) financing activities 45.9 (28.0 ) (8.1 ) 12.2 22.0 Effect of exchange rate changes on cash and cash equivalents — — (17.0 ) — (17.0 ) Net increase in cash and cash equivalents — 0.1 8.0 — 8.1 Cash and cash equivalents at beginning of year — 0.7 102.7 — 103.4 Cash and cash equivalents at end of year $ — $ 0.8 $ 110.7 $ — $ 111.5 ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS Year Ended December 31, 2015 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES $ (25.6 ) $ 77.5 $ 35.1 $ (0.5 ) $ 86.5 INVESTING ACTIVITIES Purchases of property, plant and equipment — (23.0 ) (13.8 ) — (36.8 ) Payments for capitalized internal-use software — (4.6 ) — — (4.6 ) Payments for acquisitions — (42.4 ) (3.1 ) — (45.5 ) Other — 0.1 0.3 — 0.4 Net cash used in investing activities — (69.9 ) (16.6 ) — (86.5 ) FINANCING ACTIVITIES Net payments between subsidiaries 178.1 (183.9 ) 5.8 — — Intercompany dividends — — (0.5 ) 0.5 — Proceeds from debt — 225.0 5.8 — 230.8 Repayments of debt (25.5 ) (162.9 ) (0.6 ) — (189.0 ) Repurchase of common stock (85.3 ) — — — (85.3 ) Dividends paid (18.0 ) — — — (18.0 ) Repurchase of convertible debentures conversion option (21.6 ) — — — (21.6 ) Other (2.1 ) — — — (2.1 ) Net cash provided by (used in) financing activities 25.6 (121.8 ) 10.5 0.5 (85.2 ) Effect of exchange rate changes on cash and cash equivalents — — (5.6 ) — (5.6 ) Net increase (decrease) in cash and cash equivalents — (114.2 ) 23.4 — (90.8 ) Cash and cash equivalents at beginning of year — 114.9 79.3 — 194.2 Cash and cash equivalents at end of year $ — $ 0.7 $ 102.7 $ — $ 103.4
Condensed Balance Sheet	ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING BALANCE SHEETS December 31, 2017 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated ASSETS Current assets Cash and cash equivalents $ — $ — $ 189.3 $ — $ 189.3 Accounts receivable, net — 180.1 81.6 — 261.7 Intercompany receivables — 24.0 6.7 (30.7 ) — Inventories — 135.4 68.7 — 204.1 Income tax receivable 132.3 1.3 2.0 (22.4 ) 113.2 Prepaid expenses and other current assets 4.3 26.5 20.5 — 51.3 Total current assets 136.6 367.3 368.8 (53.1 ) 819.6 Property, plant and equipment, net — 206.8 90.1 — 296.9 Goodwill — 261.0 75.1 — 336.1 Other intangible assets, net — 284.2 62.8 — 347.0 Intercompany receivables — 22.9 — (22.9 ) — Investment in subsidiaries 1,261.3 460.1 — (1,721.4 ) — Other assets 12.8 59.3 14.4 — 86.5 Total assets $ 1,410.7 $ 1,661.6 $ 611.2 $ (1,797.4 ) $ 1,886.1 LIABILITIES AND EQUITY Current liabilities Current maturities of long-term debt $ — $ 0.2 $ — $ — $ 0.2 Accounts payable 2.3 82.5 45.9 — 130.7 Intercompany payables — 6.7 24.0 (30.7 ) — Accrued expenses 22.8 90.1 46.7 (22.4 ) 137.2 Total current liabilities 25.1 179.5 116.6 (53.1 ) 268.1 Long-term debt 444.2 174.1 — — 618.3 Intercompany payables 22.9 — — (22.9 ) — Other liabilities 15.7 46.7 34.5 — 96.9 Total liabilities 507.9 400.3 151.1 (76.0 ) 983.3 Shareholders’ equity 902.8 1,261.3 460.1 (1,721.4 ) 902.8 Total liabilities and equity $ 1,410.7 $ 1,661.6 $ 611.2 $ (1,797.4 ) $ 1,886.1 ENPRO INDUSTRIES, INC. CONDENSED CONSOLIDATING BALANCE SHEETS As of December 31, 2016 (in millions) Guarantor Non-guarantor Parent Subsidiaries Subsidiaries Eliminations Consolidated ASSETS Current assets Cash and cash equivalents $ — $ 0.8 $ 110.7 $ — $ 111.5 Accounts receivable, net 0.2 151.2 56.7 — 208.1 Intercompany receivables — 10.2 4.7 (14.9 ) — Inventories — 125.9 49.5 — 175.4 Prepaid expenses and other current assets 21.3 8.9 17.4 (17.7 ) 29.9 Total current assets 21.5 297.0 239.0 (32.6 ) 524.9 Property, plant and equipment, net 0.1 148.5 66.8 — 215.4 Goodwill — 175.5 26.0 — 201.5 Other intangible assets, net — 156.5 20.4 — 176.9 Investment in GST — 236.9 — — 236.9 Intercompany receivables — 43.6 1.5 (45.1 ) — Investment in subsidiaries 681.1 236.4 — (917.5 ) — Other assets 16.4 156.2 18.2 — 190.8 Total assets $ 719.1 $ 1,450.6 $ 371.9 $ (995.2 ) $ 1,546.4 LIABILITIES AND EQUITY Current liabilities Short-term borrowings from GST $ — $ — $ 26.2 $ — $ 26.2 Notes payable to GST — 12.7 — — 12.7 Current maturities of long-term debt — 0.2 — — 0.2 Accounts payable 2.3 61.9 38.7 — 102.9 Intercompany payables — 4.7 10.2 (14.9 ) — Accrued expenses 15.3 130.1 33.3 (17.7 ) 161.0 Total current liabilities 17.6 209.6 108.4 (32.6 ) 303.0 Long-term debt 294.1 130.7 — — 424.8 Notes payable to GST — 283.2 — — 283.2 Intercompany payables 35.0 1.4 8.7 (45.1 ) — Other liabilities 13.9 144.6 18.4 — 176.9 Total liabilities 360.6 769.5 135.5 (77.7 ) 1,187.9 Shareholders’ equity 358.5 681.1 236.4 (917.5 ) 358.5 Total liabilities and equity $ 719.1 $ 1,450.6 $ 371.9 $ (995.2 ) $ 1,546.4

Selected Quarterly Financial 51

Selected Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Schedule of Selected Quarterly Financial Data	First Quarter (1) Second Quarter Third Quarter (1) Fourth Quarter (1) (in millions, except per share data) 2017 2016 2017 2016 2017 2016 2017 2016 Net sales $ 295.8 $ 294.9 $ 307.6 $ 313.2 $ 343.7 $ 292.7 $ 362.5 $ 286.9 Gross profit $ 101.6 $ 97.6 $ 104.5 $ 107.9 $ 115.2 $ 98.6 $ 123.1 $ 90.6 Net income (loss) $ 6.4 $ (46.8 ) $ 9.0 $ 3.6 $ 490.2 $ 6.0 $ 34.2 $ (2.9 ) Basic earnings (loss) per share $ 0.30 $ (2.15 ) $ 0.42 $ 0.17 $ 22.98 $ 0.28 $ 1.60 $ (0.14 ) Diluted earnings (loss) per share $ 0.30 $ (2.15 ) $ 0.41 $ 0.17 $ 22.49 $ 0.28 $ 1.57 $ (0.14 )

Overview, Basis of presentati52

Overview, Basis of presentation, Significant Accounting Policies and Recently Issued Accounting Guidance - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended									12 Months Ended
	Dec. 31, 2017	Mar. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2017	Sep. 30, 2014	Oct. 31, 2005	Oct. 30, 2005
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net Pension Gain Loss Amortization Threshold Percent										10.00%
Gross Profit	$ 123.1		$ 115.2	$ 104.5	$ 101.6	$ 90.6	$ 98.6	$ 107.9	$ 97.6	$ 444.4	$ 394.7	$ 395.5
Foreign currency transaction gains (losses)										(1.2)	(1.5)	1.8
Total research and development expenditures										$ 32.7	$ 28.9	$ 22.5
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent										35.00%	35.00%	35.00%
Retentions	0.3									$ 0.3	$ 1.3
Long-term retentions	$ 0.9									$ 0.9	$ 1.8
Percentage of inventories were valued by the LIFO method	34.00%									34.00%	38.00%
Goodwill, Impairment Loss								$ 46.1
Assets, Fair Value Disclosure, Nonrecurring													$ 1.7
Impairment of Intangible Assets, Finite-lived	$ 1.8									$ 10.1
Aggregate principal amount	624.3									624.3
Interest rate, stated percentage																3.9375%
Convertible Senior Debentures fair value															$ 111.2
Unamortized debt discount	5.8									5.8					61.3
Debt effective interest rate						9.50%						9.50%
Contractual interest coupon expense												$ 0.4
Derivative, Notional Amount	0.5									0.5	$ 2.8
Adoption of share-based payment accounting standard		$ (0.3)								0.2
Operating Leases, Future Minimum Payments Due	$ 49.4									49.4
Adjustments for New Accounting Pronouncement [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adoption of share-based payment accounting standard										$ 0.5	2.2
3.9375% Debenture [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Aggregate principal amount															$ 172.5
Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Minimum percentage of tax benefit, recognition threshold for the tax position	50.00%									50.00%
Building Improvements [Member] | Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, plant and equipment, in years										5 years
Building Improvements [Member] | Maximum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, plant and equipment, in years										25 years
Machinery and Equipment [Member] | Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, plant and equipment, in years										3 years
Machinery and Equipment [Member] | Maximum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, plant and equipment, in years										10 years
Contracts Accounted for under Percentage of Completion [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Recognized revenues										$ 76.3	86.3	67.3
Gross Profit										$ 12.9	$ 6.9	8.9
Finite-Lived Intangible Assets [Member] | Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Intangible assets estimated useful lives, minimum, in years										2 years
Finite-Lived Intangible Assets [Member] | Maximum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Intangible assets estimated useful lives, minimum, in years										21 years
Trademarks [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impairment of Intangible Assets, Finite-lived												0.9
Senior Notes [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Interest rate, stated percentage														5.875%
Debt effective interest rate														6.00%
Convertible Debentures [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Amortization of debt discount												$ 0.2

Garlock Sealing Technologies 53

Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC Garlock Sealing Technologies LLC and Garrison Litigation Management Group, Ltd., and OldCo, LLC - Reconsolidation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended	7 Months Ended	12 Months Ended
	Dec. 31, 2017	Mar. 31, 2015	Dec. 31, 2017	Jul. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reorganizations [Abstract]
Accounts Receivables	$ 22.9		$ 22.9		$ 22.9
Inventories	29.2		29.2		29.2
Property and Equipment	63.2		63.2		63.2
Goodwill	125.5		125.5		125.5
Other Intangible Assets	180.8		180.8		180.8
Other Assets	174.1		174.1		174.1
Liabilities assumed	(110.5)		(110.5)		(110.5)
Total purchase price	485.2		485.2	$ 485.2	485.2
Indefinite-lived Intangible Assets Acquired				40.4
Finite-lived Intangible Assets Acquired				140.4
Finite-Lived Customer Relationships, Gross				85.4
Other Finite-Lived Intangible Assets, Gross				50.8
Finite-Lived Contractual Rights, Gross				$ 4.2
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life				15 years
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual			81.3
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual			6.5
Pro Forma net sales					1,402.5	$ 1,337.7
Pro Forma net Income					$ 53.7	$ 520
Pro Forma Earnings Per Share, Basic					$ 2.52	$ 24.07
Pro Forma Earnings Per Share, Diluted					$ 2.46	$ 23.85
Other Nonrecurring (Income) Expense					$ 4.1
ProForma Asbestos Expenses (Credits)	(16.7)					$ 148.2
Asbestos settlement					0	80	$ 0
Pro Forma Asbestos Charges Credits						49.5
Gain on revaluation of investment in GST and OldCo					248.3
Elimination of net amounts payable to GST and OldCo at reconsolidation date		$ (2.8)			286.1
Total					534.4	0	$ 0
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	$ 0		$ 0		$ 0	$ 236.9

Garlock Sealing Technologies 54

Garlock Sealing Technologies LLC, Garrison Litigation Management Group, Ltd., and OldCo, LLC - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2017
Product Liability Contingency [Line Items]
Product Liability Contingency, Third Party Recovery		$ 15	$ 24.7
Goodwill, Purchase Accounting Adjustments	$ 7.1
Postconfirmation, Goodwill	125.5		125.5
Postconfirmation, Amortizable Intangible Assets	$ 180.8		$ 180.8

Acquisitions - Additional Infor

Acquisitions - Additional Information (Detail) - USD ($) $ in Millions	Apr. 30, 2016	Sep. 30, 2017	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Oct. 12, 2017	Jul. 31, 2015	Feb. 28, 2015
Business Combinations [Abstract]
Accounts receivable			$ 1.6
Inventories			3.4
Property, Plant, and Equipment			3.2
Goodwill			9.8
Other Intangible Assets			27.7
Other Assets			0.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities			(1.3)
Total purchase price	$ 22.6		44.6		$ 44.6	$ 28.5	$ 45.5
Restructuring Cost and Reserve [Line Items]
Business Acquisition, Revenue Reported by Acquired Entity for Last Annual Period		$ 1.5	$ 11
Business Acquisition, Percentage of Voting Interests Acquired								100.00%		100.00%
VeyanceNorthAmerican [Domain]
Restructuring Cost and Reserve [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired									100.00%
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred				$ 5.9

Other Expense - Additional Info

Other Expense - Additional Information (Detail) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2016Employees	Mar. 31, 2015USD ($)	Dec. 31, 2017USD ($)Employees	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Restructuring and Related Activities [Abstract]
Restructuring costs incurred				$ 5.1	$ 13.4	$ 6.6
Total workforce reductions | Employees		192		117
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Restructuring Charges					3.2	3.8
Severance Costs						0.6
Asset Impairment Charges				$ 2	0.8	2.7
Gain (Loss) on Contract Termination						0.1
Other Restructuring Costs						0.4
Gain on sale of businesses					0.4
Net sales of GRT					7.3	8.8
Impairment of Intangible Assets, Finite-lived	$ 1.8			10.1
Legal fees primarily related to the bankruptcy of certain subsidiaries				1.7	2.2	1.8
Environmental Remediation Expense				8.7	8.6	$ 1.4
Proceeds from Divestiture of Businesses, Net of Cash Divested					$ 3.7
Gains (Losses) on Extinguishment of Debt			$ 2.8	$ (286.1)

Other Expense - Schedule of Res

Other Expense - Schedule of Restructuring Reserves (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Beginning balance	$ 5.1	$ 0.3	$ 1.8
Provision	3.1	12.6	3.9
Payments	(6.3)	(7.8)	(5.4)
Ending balance	1.9	5.1	0.3
Personnel-Related Costs [Member]
Restructuring Cost and Reserve [Line Items]
Beginning balance	3.5	0.3	1.1
Provision	2.5	8.3	3
Payments	(5.3)	(5.1)	(3.8)
Ending balance	0.7	3.5	0.3
Facility Relocation And Closure Costs [Member]
Restructuring Cost and Reserve [Line Items]
Beginning balance	1.6	0	0.7
Provision	0.6	4.3	0.9
Payments	(1)	(2.7)	(1.6)
Ending balance	$ 1.2	$ 1.6	$ 0

Other Expense - Schedule of R58

Other Expense - Schedule of Restructuring Costs by Reportable Segment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring Expenses	$ 5.1	$ 13.4	$ 6.6
Sealing Products [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Expenses	3.6	3.3	0.4
Engineered Products [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Expenses	1.5	6.8	6.2
Power Systems [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Expenses	0	0.4	0
Corporation [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Expenses	$ 0	$ 2.9	$ 0

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income Before Income Tax Domestic and Foreign (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Domestic	$ 524.1	$ (96.4)	$ (3)
Foreign	53.4	27.7	(15.6)
Income (loss) before income taxes	$ 577.5	$ (68.7)	$ (18.6)

Income Taxes - Summary of Incom

Income Taxes - Summary of Income Tax Expense in Consolidated Statements of Operations from Continuing Operations (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Federal	$ (15.6)	$ (8.7)	$ (4)
Foreign	17.6	10.6	9.8
State	(0.2)	(0.5)	(2.4)
Current income tax expense	1.8	1.4	3.4
Federal	14.4	(25.5)	3.6
Foreign	17	0.2	(6)
State	4.5	(4.7)	1.3
Deferred income tax expense	35.9	(30)	(1.1)
Total	$ 37.7	$ (28.6)	$ 2.3

Income Taxes - Tax Benefits Rec

Income Taxes - Tax Benefits Recorded to Additional Paid in Capital (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Stock options exercised and restricted stock units vested	$ 0	$ 0	$ (1.8)
Income Tax Effects Allocated Directly to Equity	$ 0	$ 0	$ (1.8)

Income Taxes - Schedule of Defe

Income Taxes - Schedule of Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Net operating losses and tax credits	$ 89.6	$ 13.8
Accrual for post-retirement benefits other than pensions	4.1	4.5
Environmental reserves	6.5	8.7
Retained liabilities of previously owned businesses	1.2	2.1
Accruals and reserves	6.2	8.7
Pensions	0	10.2
Inventories	2.5	5.1
Asbestos settlement	0	41.4
Interest	12	9.9
Compensation and benefits	5.2	10.8
Gross deferred income tax assets	127.3	115.2
Valuation allowance	(25.7)	(20.2)
Total deferred income tax assets	101.6	95
Depreciation and amortization	(86.6)	(44.2)
GST deconsolidation gain	0	(21.4)
Joint ventures and partnerships	(0.3)	0
Asbestos settlement	(6.3)	0
Pension obligations	(1.7)	0
Total deferred income tax liabilities	(94.9)	(65.6)
Net deferred tax assets	$ 6.7
Net Deferred Tax Assets (Liabilities)		$ (29.4)

Income Taxes - Net Deferred Tax

Income Taxes - Net Deferred Tax Assets (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Deferred income taxes and income tax receivable	$ 24.8	$ 33.6
Other liabilities (non-current)	(18.1)	(4.2)
Net deferred tax assets	$ 6.7
Net Deferred Tax Assets (Liabilities)		$ (29.4)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	Feb. 19, 2018	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Subsequent Event [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			35.00%	35.00%	35.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability			$ 35
Net operating loss carryforwards during period		$ 47.6	47.6
Foreign Net Operating Loss Carryforwards, Tax Effect		12.8	12.8
Foreign Net Operating Loss Carryforwards		17.6	17.6
Indefinite operating loss carryforwards			30
State tax net operating loss carryforwards		17	17
Deferred Tax Assets, Tax Credit Carryforwards, Foreign		3.2	3.2
Transition TaxForeign Credits		43.5
Deferred Other Tax Expense (Benefit)			53.9
Tax Adjustments, Settlements, and Unusual Provisions		6.3
Deferred tax assets, valuation allowance		25.7	25.7	$ 20.2
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount		30.9
Effective tax rate impact if ultimately recognized		3.8	3.8	2.8
Foreign subsidiaries undistributed earnings		447	447
Amount of withholding tax that would be payable on remittance of the entire amount		5.4	5.4
Gross unrecognized tax benefits		3.8	3.8	2.8	$ 1.5	$ 3.1
Amount accrued for interest and penalties		0.2	0.2	0.2
Interest and penalties related to unrecognized tax benefits				$ 0.1	$ 0.1
Expected change in unrecognized tax benefits			1
Unrecognized Tax Benefits, Expected to be Recognized, Next Twelve Months		$ 0.7	$ 0.7
Subsequent Event [Member]
Subsequent Event [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Effective Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Statutory federal income tax rate	35.00%	35.00%	35.00%
US taxation of foreign profits, net of foreign tax credits	0.10%	1.10%	1.10%
Research and employment tax credits	(0.40%)	3.20%	7.70%
State and local taxes	0.20%	4.90%	4.10%
Domestic production activities	(0.40%)	1.80%	5.50%
Nondeductible goodwill impairment	0.00%	0.00%	(48.60%)
Foreign tax rate differences	(1.00%)	4.30%	(10.20%)
Uncertain tax positions and prior adjustments	(0.10%)	(1.40%)	4.30%
Statutory changes in tax rates	0.30%	0.20%	1.40%
Valuation allowance	0.20%	(6.70%)	(2.10%)
Nondeductible expenses	0.30%	(1.10%)	(6.60%)
Gain on reconsolidation of GST and OldCo	(32.40%)	0.00%	0.00%
Reconsolidation step-up of net assets of GST and OldCo to fair value	9.00%	0.00%	0.00%
Tax Act	(5.30%)	0.00%	0.00%
Other items, net	1.00%	0.40%	(3.90%)
Effective income tax rate	6.50%	41.70%	(12.30%)

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Balance at beginning of year	$ 2.8	$ 1.5	$ 3.1
Reconsolidation of GST and OldCo	0.2	0	0
Additions based on tax positions related to the current year	0.3	0.4	0.3
Additions for tax positions of prior years	1.1	1.1	0.2
Reductions as a result of a lapse in the statute of limitations	(0.3)	(0.2)	(2)
Reductions as a result of audit settlements	(0.3)	0	0
Changes due to fluctuations in foreign currency	0	0	(0.1)
Balance at end of year	$ 3.8	$ 2.8	$ 1.5

Earnings (Loss) Per Share - Sch

Earnings (Loss) Per Share - Schedule of Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Earnings Per Share [Abstract]
Net income (loss)	$ 34.2	$ 490.2	$ 9	$ 6.4	$ (2.9)	$ 6	$ 3.6	$ (46.8)	$ 539.8	$ (40.1)	$ (20.9)
Weighted-average shares - basic									21.3	21.6	22.5
Share-based awards									0.5	0	0
Weighted-average shares - diluted									21.8	21.6	22.5
Basic (in usd per share)	$ 1.60	$ 22.98	$ 0.42	$ 0.30	$ (0.14)	$ 0.28	$ 0.17	$ (2.15)	$ 25.28	$ (1.86)	$ (0.93)
Diluted (in usd per share)	$ 1.57	$ 22.49	$ 0.41	$ 0.30	$ (0.14)	$ 0.28	$ 0.17	$ (2.15)	$ 24.76	$ (1.86)	$ (0.93)
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount										0.2	0.8

Inventories - Schedule of Inven

Inventories - Schedule of Inventories (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Finished products	$ 121.4	$ 108.1
Work in process	33	23.7
Raw materials and supplies	59.2	49.3
Inventory Gross	213.6	181.1
Reserve to reduce certain inventories to LIFO basis	(10.2)	(12.1)
Manufacturing inventories	203.4	169
Incurred costs related to long-term contracts	0.7	13.6
Progress payments related to long-term contracts	0	(7.2)
Net balance associated with completed-contract inventories	0.7	6.4
Total inventories	$ 204.1	$ 175.4

Long-Term Contracts Long-Term69

Long-Term Contracts Long-Term Contracts - Costs and Billings on Uncompleted Contracts - Schedule of Information Regarding Contracts Accounted for Under Percentage-of-Completion Method (Detail) - Acrrued Expenses [Member] - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cumulative Revenues Recognized On Uncompleted POC Contracts	$ 348.2	$ 260.7
Cumulative Billings on Uncompleted POC Contracts	300.7	231.6
Revenues Billings On Uncompleted Contracts	$ 47.5	$ 29.1

Long-Term Contracts Long-Term70

Long-Term Contracts Long-Term Contracts - Cost and Billings on Uncompleted Contracts - Schedule of Uncompleted Contracts Reflected in Consolidated Balance Sheets (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Incurred costs related to long-term contracts	$ 0.7	$ 13.6
Progress payments related to long-term contracts	0	(7.2)
Retainage Deposit	2.9	0.8
Accounts Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable (POC revenue recognized In excess of Billings)	51.7	31.4
Acrrued Expenses [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued expenses (billings in excess of POC revenue recognized)	(4.2)	(2.3)
Revenues Billings On Uncompleted Contracts	47.5	29.1
Incurred costs related to long-term contracts	0	0.1
Progress payments related to long-term contracts	0	(1)
Billings in Excess of Cost	$ 0	$ (0.9)

Property, Plant and Equipment -

Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Land	$ 13.9	$ 11
Buildings and improvements	141.5	112.8
Machinery and equipment	448.7	367.8
Construction in progress	31.9	31.2
Gross	636	522.8
Less accumulated depreciation	(339.1)	(307.4)
Total	$ 296.9	$ 215.4

Goodwill and Other Intangible72

Goodwill and Other Intangible Assets - Schedule of Changes in Net Carrying Value of Goodwill by Reportable Segment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 201.5	$ 195.9
Foreign currency translation	(0.7)	(1.5)
Goodwill, Written off Related to Sale of Business Unit		(0.7)
Acquisitions	9.8	7.8
Goodwill, ending balance	336.1	201.5
Goodwill, Other Increase (Decrease)	125.5
Operating Segments [Member] | Sealing Products [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	185.3	179.7
Foreign currency translation	(0.7)	(1.5)
Goodwill, Written off Related to Sale of Business Unit		(0.7)
Acquisitions	9.8	7.8
Goodwill, ending balance	313.2	185.3
Goodwill, Other Increase (Decrease)	118.8
Operating Segments [Member] | Engineered Products [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	9.1	9.1
Foreign currency translation	0	0
Acquisitions	0	0
Goodwill, ending balance	10.9	9.1
Goodwill, Other Increase (Decrease)	1.8
Operating Segments [Member] | Power Systems [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	7.1	7.1
Goodwill, ending balance	12	$ 7.1
Goodwill, Other Increase (Decrease)	$ 4.9

Goodwill and Other Intangible73

Goodwill and Other Intangible Assets - Schedule of Identifiable Intangible Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Amortized, Gross Carrying Amount	$ 488.7	$ 337.8
Amortized, Accumulated Amortization	221	194.7
Intangible Assets, Gross (Excluding Goodwill)	568	371.6
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Amortized, Gross Carrying Amount	311.2	216.2
Amortized, Accumulated Amortization	138	122
Existing technology [Member]
Finite-Lived Intangible Assets [Line Items]
Amortized, Gross Carrying Amount	113	63
Amortized, Accumulated Amortization	37.5	31
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Amortized, Gross Carrying Amount	35.8	35.4
Amortized, Accumulated Amortization	22.3	19.6
Other [Member]
Finite-Lived Intangible Assets [Line Items]
Amortized, Gross Carrying Amount	28.7	23.2
Amortized, Accumulated Amortization	$ 23.2	$ 22.1

Goodwill and Other Intangible74

Goodwill and Other Intangible Assets us-gaap_ScheduleOfIndefiniteLivedIntangibleAssetsTable (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Trademarks [Member]
Indefinite-lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	$ 79.3	$ 33.8

Goodwill and Other Intangible75

Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Amortization expense	$ 24.7	$ 21	$ 21.9
Sealing Products [Member]
Segment Reporting Information [Line Items]
Goodwill, Impaired, Accumulated Impairment Loss	27.8	27.8	27.8
Engineered Products [Member]
Segment Reporting Information [Line Items]
Goodwill, Impaired, Accumulated Impairment Loss	$ 154.8	$ 154.8	$ 108.7

Goodwill and Other Intangible76

Goodwill and Other Intangible Assets - Schedule of Estimated Amortization Expense of Intangible Assets (Detail) $ in Millions	Dec. 31, 2017USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2,018	$ 29.8
2,019	29.1
2,020	28.7
2,021	26.3
2,022	$ 20.9

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Salaries, wages and employee benefits	$ 63.7	$ 40
Interest	8.6	38.1
Customer advances	7.1	5.3
Income and other taxes	14.3	11.2
Other	42.9	36.4
Total accrued expenses	$ 136.6	$ 131

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jan. 01, 2010	Oct. 30, 2005
Related Party Transaction [Line Items]
Short-term borrowings from GST	$ 0	$ 26.2
Amended and Restated Promissory Note	0	295.9
Interest rate, stated percentage					3.9375%
Interest	46.4	41	$ 36.4
Intercompany notes, interest paid in kind added to principal balance, value	0	12.7
Garlock Sealing Technologies [Member]
Related Party Transaction [Line Items]
Short-term borrowings from GST		26.2
Interest	$ 19.3	18.4
Majority-Owned Subsidiary, Unconsolidated [Member]
Related Party Transaction [Line Items]
Amended and Restated Promissory Note				$ 73.4
Subsidiary of Common Parent [Member]
Related Party Transaction [Line Items]
Amended and Restated Promissory Note				$ 153.8
Intercompany Notes [Member]
Related Party Transaction [Line Items]
Interest rate, stated percentage	11.00%
Intercompany notes, interest payable in cash, percentage	6.50%
Intercompany notes, interest paid in kind added to principal amount, percentage	4.50%
Intercompany notes, interest paid in kind added to principal balance, value	$ 13.4	$ 12.7

Related Party Transactions - Sc

Related Party Transactions - Schedule of Amounts Included in Financial Statements Arising from Transactions with GST (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Related Party Transaction [Line Items]
Due from GST	$ 0	$ 0
Accrued interest to GST	8.6	38.1
Accounts Receivable [Member]
Related Party Transaction [Line Items]
Due from GST		21.4
Deferred Income Taxes and Income Taxes Receivable [Member]
Related Party Transaction [Line Items]
Income tax receivable from GST		119
Other Assets [Member]
Related Party Transaction [Line Items]
Due from GST		1.4
Accounts Payable [Member]
Related Party Transaction [Line Items]
Due to GST		6.3
Accrued Expenses [Member]
Related Party Transaction [Line Items]
Accrued interest to GST		32.6
Net Sales [Member]
Related Party Transaction [Line Items]
Sales to GST	20.8	28	$ 30.6
Cost of Sales [Member]
Related Party Transaction [Line Items]
Purchases from GST	12.2	17.7	20.7
Interest Expense [Member]
Related Party Transaction [Line Items]
Interest expense to GST	$ 20.6	$ 33.5	$ 31.6

Long-Term Debt - Schedule of Lo

Long-Term Debt - Schedule of Long Term Debt (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term debt	$ 618.5	$ 425
Less current maturities of long-term debt	0.2	0.2
Long-term debt, net	618.3	424.8
Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Senior Notes	444.2	294.1
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt	173.5	130
Other Notes Payables [Member]
Debt Instrument [Line Items]
Long-term debt	$ 0.8	$ 0.9

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail) - USD ($)	Aug. 28, 2014	Sep. 30, 2014	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2015	Aug. 24, 2014	Oct. 31, 2005	Oct. 30, 2005
Line of Credit Facility [Line Items]
Unamortized debt discount			$ 5,800,000				$ 61,300,000
Debt Instrument, Interest Rate, Stated Percentage								3.9375%
Debt Instrument, Interest Rate, Effective Percentage					9.50%
Debt Instrument, Term	5 years
Credit facility maximum availability						$ 300,000,000
Adjusted LIBOR rate interest spread			1.00%
Credit facility borrowing capacity			$ 111,500,000
Letter of credit outstanding			15,000,000
Long-term Line of Credit			173,500,000
Debt Issuance Costs, Line of Credit Arrangements, Gross			$ 2,400,000
Senior Notes [Member]
Line of Credit Facility [Line Items]
Senior Notes				$ 150,000,000
Debt Instrument, Interest Rate, Stated Percentage		5.875%
Debt Instrument, Unamortized Premium				$ 1,500,000
Debt Instrument, Interest Rate, Effective Percentage				5.66%
Base Rate [Member]
Line of Credit Facility [Line Items]
Adjusted LIBOR rate interest spread			2.00%
Senior Notes [Member]
Line of Credit Facility [Line Items]
Senior Notes		$ 300,000,000
Payments of Debt Issuance Costs		$ 2,400,000
Debt Instrument, Interest Rate, Stated Percentage		5.875%
Debt Instrument, Interest Rate, Effective Percentage		6.00%

Long Term Debt - Schedule of Fu

Long Term Debt - Schedule of Future Principal Payments on Long-Term Debt (Detail) $ in Millions	Dec. 31, 2017USD ($)
Debt Disclosure [Abstract]
2,018	$ 0.2
2,019	173.7
2,020	0.2
2,021	0.1
2,022	450
Thereafter	0.1
Total	$ 624.3

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items]
Assets measured at fair value	$ 7.8	$ 33
Level 1 [Member] | Bank Time Deposits [Member]
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items]
Cash equivalents	0	26
Level 1 [Member] | Deferred Compensation [Member]
Fair Value, Option, Qualitative Disclosures Related to Election [Line Items]
Assets measured at fair value	7.8	7
Liabilities measured at fair value	$ 8.9	$ 8.3

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Carrying Value of Financial Instruments (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Long-term debt, Carrying Value	$ 618.5	$ 425
Notes payable to GST, Carrying Value	0	295.9
Long-term Debt, Fair Value	645.6	439.1
Notes payable to GST, Fair Value	$ 0	$ 302.7

Fair Value Measurements Fair Va

Fair Value Measurements Fair Value Measurements - Assets Measured on a Nonrecurring Basis (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Sep. 30, 2017	Jul. 31, 2017
Fair Value Disclosures [Abstract]
Assets, Fair Value Disclosure, Nonrecurring			$ 1.7
Impairment of Intangible Assets, Finite-lived	$ 1.8	$ 10.1
Postconfirmation, Stockholders' Equity	$ 485.2	$ 485.2		$ 485.2

Pensions and Postretirement B86

Pensions and Postretirement Benefits - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)BasisPoint	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2006
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 350.7	$ 256.9
Minimum age of salaried employees with defined pension plans, in years				40 years
Percentage of matching contributions for eligible employees of their eligible earnings	6.00%
Additional employer contribution for those employees whose defined pension plan benefits were frozen	2.00%
Matching contributions under plans	$ 11.5	9.6	$ 9.2
Cash contributed by the entity to its U.S. pension plans	8.8	14.8	$ 0
Projected benefit obligation for defined benefit pension plans	308.6	286.7
Accumulated benefit obligation for defined benefit pension plans	302.6	279.7
Fair value of plan assets for defined benefit pension plans	289.7	254.3
Net Loss [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Estimated prior service cost for other defined benefit postretirement plans that will be amortized from AOCI into net periodic benefit cost over next fiscal year	5.4
Prior Service Cost [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Estimated prior service cost for other defined benefit postretirement plans that will be amortized from AOCI into net periodic benefit cost over next fiscal year	0.3
Defined Benefit Pension Plans [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Accumulated benefit obligation for all existing plans	$ 361.7	$ 281.6
Discount rate	3.75%
Basis point decrease (increase) in discount rate | BasisPoint	25
Pension expense per year	$ 0.9
Domestic Plan [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Company anticipates future contributions	20
Foreign Plan [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Company anticipates future contributions	$ 0.8

Pensions and Postretirement B87

Pensions and Postretirement Benefits - Schedule of Change in Projected Benefit Obligations (Detail) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligations at beginning of year	$ 289.7	$ 289.7	$ 283.4
Service cost		4.5	4.3
Interest cost		12.9	12.7
Actuarial loss (gain)		16.1	8.9
Amendment		0.2
Benefit Paid		13.6	18.1
Reconsolidation of GST and OldCo		58.8	0
Other		0.6	(1.5)
Projected benefit obligations at end of year		369.2	289.7
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligations at beginning of year	3.2	3.2	3.4
Service cost		0.1	0.1
Interest cost		0.1	0.2
Actuarial loss (gain)		0	(0.3)
Amendment		0	0
Benefit Paid		0.9	0.2
Reconsolidation of GST and OldCo		2.1
Other	$ 0.1
Projected benefit obligations at end of year		$ 4.7	$ 3.2

Pensions and Postretirement B88

Pensions and Postretirement Benefits - Schedule of Change in Plan Assets and Underfunded Status at End of Year (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at end of year	$ 350.7	$ 256.9
Fair value of plan assets at beginning of year	256.9
Pension Plan [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at end of year	350.7	256.9
Actual return on plan assets	42.3	17.3
Administrative expenses	(0.8)	(0.4)
Benefits paid	(13.6)	(18.1)
Company contributions	9.4	15.6
Reconsolidation of GST and OldCo	56.5	0
Fair value of plan assets at beginning of year	$ 256.9	$ 242.5

Pensions and Postretirement B89

Pensions and Postretirement Benefits - Schedule of Projected Benefit Obligations Amounts Recognized in Consolidated Balance Sheets (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Assets for Plan Benefits, Defined Benefit Plan	$ 0.8	$ 0
Current liabilities	(0.5)	(0.4)
Long-term liabilities	(18.8)	(32.4)
Amounts recognized in the consolidated balance sheets	(18.5)	(32.8)
Other Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Assets for Plan Benefits, Defined Benefit Plan	0	0
Current liabilities	(0.3)	(0.1)
Long-term liabilities	(4.4)	(3.1)
Amounts recognized in the consolidated balance sheets	$ (4.7)	$ (3.2)

Pensions and Postretirement B90

Pensions and Postretirement Benefits - Schedule of Pre-Tax Charges Recognized in Accumulated Other Comprehensive Income Loss (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Net actuarial (gain) loss	$ 65.3	$ 78.4
Prior service cost	1.4	1.2
Pre-tax charges recognized in accumulated other comprehensive income (loss)	66.7	79.6
Other Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Net actuarial (gain) loss	(0.3)	(0.4)
Prior service cost	0.3	0.4
Pre-tax charges recognized in accumulated other comprehensive income (loss)	$ 0	$ 0

Pensions and Postretirement B91

Pensions and Postretirement Benefits - Schedule of Net Periodic Benefit Cost (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Pension Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Service cost	$ 4.5	$ 4.3
Interest cost	12.9	12.7
Pension Benefits [Member] | Net Periodic Benefit Cost [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Service cost	4.5	4.3	$ 4.9
Interest cost	12.9	12.7	12
Expected return on plan assets	(20.1)	(17.2)	(18.2)
Amortization of prior service cost	0.3	0.2	0.2
Amortization of net loss	7.3	6.9	6.9
Curtailment	(0.1)	(0.1)
Deconsolidation of GST	(0.3)	(0.9)	(0.7)
Net periodic benefit cost	4.5	5.9	5.1
Other Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Service cost	0.1	0.1
Interest cost	0.1	0.2
Other Benefits [Member] | Net Periodic Benefit Cost [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Service cost	0.1	0.1	0.1
Interest cost	0.1	0.2	0.2
Amortization of prior service cost	0.1	0.1	0
Curtailment	0	(0.3)	0
Net periodic benefit cost	$ 0.3	$ 0.1	$ 0.3

Pensions and Postretirement B92

Pensions and Postretirement Benefits - Schedule of Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Other adjustment	$ (5.2)	$ 7.8	$ 3.4
Pension Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Net loss (gain)	(5.8)	8.2	3.3
Prior service cost	0.5	0	0
Amortization of net loss	(7.3)	(6.9)	(6.9)
Amortization of prior service cost	(0.3)	(0.2)	(0.2)
Other adjustment	0	0	(0.1)
Total recognized in other comprehensive income	(12.9)	1.1	(3.9)
Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax	(8.4)	7	1.2
Other Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Net loss (gain)	0.1	(0.4)	(0.4)
Prior service cost	0	0	0.6
Amortization of prior service cost	(0.1)	(0.1)	0
Other adjustment	0	0.3	0
Total recognized in other comprehensive income	0	(0.2)	0.2
Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax	$ 0.3	$ (0.1)	$ 0.5

Pensions and Postretirement B93

Pensions and Postretirement Benefits - Schedule of Weighted-Average Assumptions Used to Determine Benefit Obligations and Net Periodic Benefit Cost (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Pension Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Benefit Obligations, Discount rate	3.75%	4.25%	4.63%
Benefit Obligations, Rate of compensation increase	3.00%	3.00%	3.00%
Net Periodic Benefit Cost, Discount rate	4.25%	4.63%	4.25%
Net Periodic Benefit Cost, Expected long-term return on plan assets	7.25%	7.25%	7.25%
Net Periodic Benefit Cost, Rate of compensation increase	3.00%	3.00%	3.00%
Other Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Benefit Obligations, Discount rate	3.75%	4.25%	4.63%
Benefit Obligations, Rate of compensation increase	4.00%	4.00%	4.00%
Net Periodic Benefit Cost, Discount rate	4.25%	4.63%	4.25%
Net Periodic Benefit Cost, Rate of compensation increase	4.00%	4.00%	4.00%

Pensions and Postretirement B94

Pensions and Postretirement Benefits - Schedule of Assumed Health Care Cost Trend Rates (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Retirement Benefits [Abstract]
Health care cost trend rate assumed for next year	8.00%	8.00%
Rate to which the cost trend rate is assumed to decline (the ultimate rate)	4.50%	4.50%
Year that the rate reaches the ultimate trend rate	2,025	2,024

Pensions and Postretirement B95

Pensions and Postretirement Benefits - Schedule of Asset Allocation for Pension Plans and Target Allocation by Asset Category (Detail)	Dec. 31, 2017	Dec. 31, 2016
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation	100.00%
Plan Assets	100.00%	100.00%
Equity Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation	30.00%
Plan Assets	30.00%	40.00%
Fixed Income [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation	70.00%
Plan Assets	70.00%	60.00%

Pensions and Postretirement B96

Pensions and Postretirement Benefits - Schedule of Fair Value of Plan Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan investment	$ 350.7	$ 256.9
Mutual Funds - U.S. Equity [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan investment	61.6	65.7
Fixed Income Treasury And Money Market [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan investment	244.6	153.3
Mutual Funds - International Equity [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan investment	43.3	37
Cash Equivalents [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan investment	$ 1.2	$ 0.9

Pensions and Postretirement B97

Pensions and Postretirement Benefits - Schedule of Benefit Payments Reflecting Expected Future Service as Appropriate Expected to be Paid (Detail) $ in Millions	Dec. 31, 2017USD ($)
Pension Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
2,018	$ 16.4
2,019	17.1
2,020	18
2,021	18.8
2,022	19.6
Years 2021 - 2025	111.2
Other Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
2,018	0.5
2,019	0.5
2,020	1.5
2,021	0.5
2,022	0.4
Years 2021 - 2025	$ 1.5

Shareholders' Equity (Details)

Shareholders' Equity (Details) - USD ($) $ / shares in Units, shares in Millions	Feb. 19, 2018	Apr. 30, 2015	Dec. 31, 2017	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Oct. 31, 2015	Feb. 28, 2015
Subsequent Event [Line Items]
Stock Repurchased During Period, Shares		1.2		0.1	0.2	0.6
Treasury Stock, Value, Acquired, Cost Method				$ 6,000,000	$ 11,500,000	$ 29,700,000
Payments for Repurchase of Common Stock			$ 5,300,000		11,500,000	30,400,000	$ 85,300,000
Payments of Ordinary Dividends, Common Stock					$ 19,000,000	$ 18,100,000	$ 18,000,000
Stock Repurchase Program, Authorized Amount								$ 50,000,000	$ 80,000,000
Repurchase Average Price Per Share (in dollars per share)		$ 66.76
Subsequent Event
Subsequent Event [Line Items]
Cash dividend declared (in dollars per share)	$ 0.24

Accumulated Other Comprehensi99

Accumulated Other Comprehensive Income (Loss) - Summary of Changes in Accumulated Other Comprehensive Loss by Components (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehinsive Income [Roll Forward]
Beginning balance	$ (70.9)	$ (54.1)	$ (34.1)
Other Comprehensive Income (Loss), before Reclassifications	17.6	21.1	23.7
Amount Reclassified from Accumulated Other Comprehensive Income (loss)	(4.9)	4.3	3.7
Net Current-Period Other Comprehensive Income (Loss)	22.5	(16.8)	(20)
Ending balance	(48.4)	(70.9)	(54.1)
Unrealized Translation Adjustments [Member]
Accumulated Other Comprehinsive Income [Roll Forward]
Beginning balance	(21.2)	(4.9)	17
Other Comprehensive Income (Loss), before Reclassifications	14.4	16.1	21.9
Amount Reclassified from Accumulated Other Comprehensive Income (loss)	0	(0.2)	0
Net Current-Period Other Comprehensive Income (Loss)	14.4	(16.3)	(21.9)
Ending balance	(6.8)	(21.2)	(4.9)
Pension and Other Postretirement Plans [Member]
Accumulated Other Comprehinsive Income [Roll Forward]
Beginning balance	(49.7)	(49.2)	(51.1)
Other Comprehensive Income (Loss), before Reclassifications	3.2	5	1.8
Amount Reclassified from Accumulated Other Comprehensive Income (loss)	(4.9)	4.5	3.7
Net Current-Period Other Comprehensive Income (Loss)	8.1	(0.5)	1.9
Ending balance	$ (41.6)	$ (49.7)	$ (49.2)

Accumulated Other Comprehens100

Accumulated Other Comprehensive Loss - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income tax benefit (expense)									$ (37.7)	$ 28.6	$ (2.3)
Net income (loss)	$ 34.2	$ 490.2	$ 9	$ 6.4	$ (2.9)	$ 6	$ 3.6	$ (46.8)	539.8	(40.1)	(20.9)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Release of unrealized currency translation adjustment upon sale of investment in foreign entity, net of tax									0	(0.2)	0
Reclassification out of Accumulated Other Comprehensive Income [Member] | Pension and Other Postretirement Plans [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Actuarial losses									7.3	6.6	6.9
Prior service costs									0.4	0.3	0.2
Total before tax									7.7	6.9	7.1
Income tax benefit (expense)									(2.8)	(2.4)	(3.4)
Net income (loss)									$ 4.9	$ 4.5	$ 3.7

Equity Compensation Plan - Addi

Equity Compensation Plan - Additional Information (Detail) - USD ($)	Feb. 13, 2017	Feb. 23, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares pursuant to various market and performance-based incentive awards			6,200,000
Shares available for future awards			700,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate	34.86%	32.80%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	1.45%	0.88%
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Total Shareholder Return Correlation	62.59%	58.95%
Percentage of fair market value on the date of grant			100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price			$ 42.24
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term			3 years 1 month 13 days
Annual amount of shares granted to non-employee directors, value			$ 90,000	$ 95,000
Employee Service Share-based Compensation, Cash Flow Effect, Cash Used to Settle Awards			$ 1,400,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units awards vest period			3 years
Unrecognized compensation cost			$ 5,200,000
Unrecognized compensation cost expected to be recognized over a weighted average period, years			1 year 4 months 6 days
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost			$ 3,000,000
Unrecognized compensation cost expected to be recognized over a weighted average period, years			1 year 4 months 5 days
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate	31.23%	27.36%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	1.23%	1.82%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	1.45%	0.88%
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period			10 years
Non-Employee Directors Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense			$ 700,000	$ 1,200,000	$ 700,000

Equity Compensation Plan - Summ

Equity Compensation Plan - Summary of Restricted Share Units Activity, Performance Share Activity and Restricted Stock Activity (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Nonvested shares, Beginning Balance	262,022	264,031	269,585
Granted, Shares	77,120	111,320	94,623
Vested, Shares	(79,417)	(59,104)	(38,457)
Forfeited, Shares	(17,607)	(42,090)	(34,157)
Shares settled for cash, shares	(6,561)	(12,135)	(27,563)
Nonvested Shares, Ending Balance	235,557	262,022	264,031
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Nonvested, Weighted-Average Grant Date Fair Value, Beginning Balance	$ 59.43	$ 61.74	$ 54.60
Granted, Weighted-Average Grant Date Fair Value	68.55	44.29	63.98
Vested, Weighted-Average Grant Date Fair Value	64.16	45.20	37.67
Forfeited, Weighted-Average Grant Date Fair Value	56.32	58.48	59.34
Shares settled for cash, Weighted-Average Grant Date Fair Value	54.29	44.63	37.65
Nonvested, Weighted-Average Grant Date Fair Value, Ending Balance	$ 57.87	$ 59.43	$ 61.74
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Nonvested shares, Beginning Balance	283,515	198,402	227,220
Granted, Shares	84,534	199,965	115,197
Vested, Shares	(76,487)	0	(98,230)
Forfeited, Shares	(8,823)	(37,542)	(3,398)
Achievement level adjustment, shares	(12,140)	(77,310)	(42,387)
Nonvested Shares, Ending Balance	270,599	283,515	198,402
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Nonvested, Weighted-Average Grant Date Fair Value, Beginning Balance	$ 54.84	$ 67.22	$ 55.65
Granted, Weighted-Average Grant Date Fair Value	76.93	49.68	68.31
Vested, Weighted-Average Grant Date Fair Value	63.81	0	44.63
Forfeited, Weighted-Average Grant Date Fair Value	61.43	54.66	60.09
Achievement level adjustment, Weighted-Average Grant Date Fair Value	63.81	71.83	44.63
Nonvested, Weighted-Average Grant Date Fair Value, Ending Balance	$ 61.92	$ 54.84	$ 67.22
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Nonvested shares, Beginning Balance	0	11,330	11,330
Granted, Shares	0	0	0
Vested, Shares	0	(11,330)	0
Forfeited, Shares	0	0	0
Nonvested Shares, Ending Balance	0	0	11,330
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Nonvested, Weighted-Average Grant Date Fair Value, Beginning Balance	$ 0	$ 55.09	$ 55.09
Granted, Weighted-Average Grant Date Fair Value	0	0	0
Vested, Weighted-Average Grant Date Fair Value	0	55.09	0
Forfeited, Weighted-Average Grant Date Fair Value	0	0	0
Nonvested, Weighted-Average Grant Date Fair Value, Ending Balance	$ 0	$ 0	$ 55.09

Equity Compensation Plan - S103

Equity Compensation Plan - Summary of Option Activity Under Plan (Detail)	12 Months Ended
	Dec. 31, 2017$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Share Options Outstanding, Beginning Balance | shares	79,505
Share Options Outstanding, Exercised | shares	(61,318)
Share Options Outstanding, Ending Balance | shares	18,187
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Exercise Price, Beginning Balance | $ / shares	$ 36.31
Weighted Average Exercise Price, Exercised | $ / shares	34.55
Weighted Average Exercise Price, Ending Balance | $ / shares	$ 42.24

Equity Compensation Plan - Sche

Equity Compensation Plan - Schedule of Intrinsic Value Related to Stock Options (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Options outstanding	$ 0.9	$ 2.5	$ 0.9
Options exercisable	0.9	2.5	0.9
Options exercised	$ 2.2	$ 0.7	$ 0.1

Equity Compensation Plan - S105

Equity Compensation Plan - Schedule of Equity Based Compensation (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Compensation expense	$ 9.5	$ 5.1	$ 4.1
Related income tax benefit	$ 3.6	$ 1.9	$ 1.5

Business Segment Information -

Business Segment Information - Additional Information (Detail) - Segment	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting [Abstract]
Percentage of net sales	10.00%	10.00%	10.00%
Number Of Operating Segments	3

Business Segment Information107

Business Segment Information - Schedule of Segment Operating Results and Other Financial Data (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total product segment sales	$ 362.5	$ 343.7	$ 307.6	$ 295.8	$ 286.9	$ 292.7	$ 313.2	$ 294.9	$ 1,309.6	$ 1,187.7	$ 1,204.4
Segment profit									101.2	(4.7)	37.6
Goodwill and Intangible Asset Impairment									(10.1)	0	(47)
Asbestos settlement									0	(80)	0
Gain on reconsolidation of GST and OldCo									534.4	0	0
Other expense, net									(8.7)	(8.9)	(4.1)
Income from continuing operations before income taxes									577.5	(68.7)	(18.6)
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Segment profit									(34.3)	(30)	(28.2)
Goodwill and Intangible Asset Impairment									(10.1)	0	(47)
Asbestos settlement									0	(80)	0
Interest expense, net									(49.4)	(55.1)	(52.1)
Gain on reconsolidation of GST and OldCo									534.4
Other expense, net									(12.8)	(14.8)	(9.1)
Income from continuing operations before income taxes									577.5	(68.7)	(18.6)
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Total product segment sales									4	3.3	3.6
Operating Segments [Member]
Segment Reporting Information [Line Items]
Segment profit									149.7	111.2	117.8
Operating Segments [Member] | Sealing Products [Member]
Segment Reporting Information [Line Items]
Total product segment sales									804.3	705.6	705.6
Segment profit									90.9	81.8	84.3
Operating Segments [Member] | Engineered Products [Member]
Segment Reporting Information [Line Items]
Total product segment sales									301.1	277.1	297.8
Segment profit									29.8	12.4	6.4
Operating Segments [Member] | Power Systems [Member]
Segment Reporting Information [Line Items]
Total product segment sales									208.2	208.3	204.6
Segment profit									29	17	27.1
Operating Segments [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total product segment sales									$ 1,313.6	$ 1,191	$ 1,208

Business Segment Information108

Business Segment Information - Schedule of Segment Related Capital Expenditure, Depreciation and Amortization on those Expenditures (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Related Capital Expenditure And Depreciation And Amortization On Those Expenditures [Line Items]
Total capital expenditures	$ 41	$ 35.8	$ 36.8
Total depreciation and amortization	63.8	57.1	58.1
Corporate [Member]
Segment Related Capital Expenditure And Depreciation And Amortization On Those Expenditures [Line Items]
Total capital expenditures	0	0	0.1
Total depreciation and amortization	0	0.1	0.3
Power Systems [Member]
Segment Related Capital Expenditure And Depreciation And Amortization On Those Expenditures [Line Items]
Total capital expenditures	10.7	5.7	4.9
Total depreciation and amortization	5.2	4.4	4.1
Engineered Products [Member]
Segment Related Capital Expenditure And Depreciation And Amortization On Those Expenditures [Line Items]
Total capital expenditures	9.9	7.2	14.8
Total depreciation and amortization	16.8	17.5	19.4
Sealing Products [Member]
Segment Related Capital Expenditure And Depreciation And Amortization On Those Expenditures [Line Items]
Total capital expenditures	20.4	22.9	17
Total depreciation and amortization	$ 41.8	$ 35.1	$ 34.3

Business Segment Information109

Business Segment Information - Schedule of Net Sales by Geographical Area (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule Of Net Sales By Geographical Segment [Line Items]
Net Sales by Geographic Area	$ 362.5	$ 343.7	$ 307.6	$ 295.8	$ 286.9	$ 292.7	$ 313.2	$ 294.9	$ 1,309.6	$ 1,187.7	$ 1,204.4
United States [Member]
Schedule Of Net Sales By Geographical Segment [Line Items]
Net Sales by Geographic Area									750.6	682.4	696.2
Europe [Member]
Schedule Of Net Sales By Geographical Segment [Line Items]
Net Sales by Geographic Area									292.6	289.9	289.5
Other Foreign [Member]
Schedule Of Net Sales By Geographical Segment [Line Items]
Net Sales by Geographic Area									$ 266.4	$ 215.4	$ 218.7

Business Segment Information110

Business Segment Information - Schedule of Assets and Long Lived Assets Segment (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Schedule Of Assets By Segment [Line Items]
Assets	$ 1,886.1	$ 1,546.4
Property, Plant and Equipment, Net	296.9	215.4
United States [Member]
Schedule Of Assets By Segment [Line Items]
Property, Plant and Equipment, Net	206.9	148.6
France [Member]
Schedule Of Assets By Segment [Line Items]
Property, Plant and Equipment, Net	26.5	23
Other Europe [Member]
Schedule Of Assets By Segment [Line Items]
Property, Plant and Equipment, Net	23.4	20.7
Other Foreign [Member]
Schedule Of Assets By Segment [Line Items]
Property, Plant and Equipment, Net	40.1	23.1
Operating Segments [Member] | Sealing Products [Member]
Schedule Of Assets By Segment [Line Items]
Assets	1,078	636.4
Operating Segments [Member] | Engineered Products [Member]
Schedule Of Assets By Segment [Line Items]
Assets	229.2	210
Operating Segments [Member] | Power Systems [Member]
Schedule Of Assets By Segment [Line Items]
Assets	210.8	164.8
Corporate, Non-Segment [Member]
Schedule Of Assets By Segment [Line Items]
Assets	$ 368.1	$ 535.2

Subsidiary Asbestos Bankrupt111

Subsidiary Asbestos Bankruptcies Subsidiary Asbestos Bankruptcies - Additional Information (Details) - USD ($)	Nov. 11, 2016	Jan. 14, 2015	May 29, 2014	Dec. 31, 2017	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
ReorganizationItems [Line Items]
Litigation Settlement, Amount Awarded to Other Party	$ 20,000,000
Loss Contingency Accrual, Payments				$ 78,800,000	$ 350,000,000
Asbestos settlement							$ 0	$ 80,000,000	$ 0
Option Indexed to Issuer's Equity, Strike Price						$ 1
Product Liability Contingency, Accrual, Discount Rate	4.50%
Loss Contingency Accrual Payments Future Interest Requirements				1,200,000			1,200,000
GST, LLC [Member]
ReorganizationItems [Line Items]
Liability For Asbestos and Environmental Claims, Period for Additional Contributions		7 years
Loss Contingency Accrual, Payments					16,700,000	$ 17,000,000
Liabilities Subject to Compromise, Asbestos Obligations								387,000,000	$ 337,500,000
Liability for Asbestos and Environmental Claims, Gross								370,000,000
Coltec Industries Inc. [Member]
ReorganizationItems [Line Items]
Litigation Settlement, Amount Awarded to Other Party								110,000,000
EnPro And Subsidiaries And GST [Member]
ReorganizationItems [Line Items]
Litigation Settlement, Amount Awarded to Other Party								$ 480,000,000
New Coltec [Member]
ReorganizationItems [Line Items]
Litigation Settlement, Amount Awarded to Other Party							60,000,000
Option Indexed To Issuers Equity Settlement Alternatives Amount At Fair value				$ 20,000,000			$ 20,000,000
Percentage of Outstanding Voting Equity in GST LLC and GLMG							50.10%
Future Claim Representative [Member] | GST, LLC [Member]
ReorganizationItems [Line Items]
Plan of Reorganization, Loss Contingency Trust, Contribution, Amended Proposal, Administrative and Litigation Costs		$ 30,000,000
Litigation Settlement, Amount Awarded to Other Party		77,500,000
Asbestos Issue [Member] | OldCo [Member]
ReorganizationItems [Line Items]
Loss Contingency Accrual, Payments					$ 50,000,000
Asbestos Issue [Member] | GST, LLC [Member]
ReorganizationItems [Line Items]
Plan of Reorganization, Loss Contingency Trust, Contribution, Amended Proposal, Administrative and Litigation Costs			$ 220,000,000
Plan of Reorganization, Loss Contingency Trust, Contribution, Amended Proposal, Contingent Supplementary Contributions, Low Range of Possible Outcome		1
Asbestos Issue [Member] | Coltec Industries Inc. [Member]
ReorganizationItems [Line Items]
Plan of Reorganization, Loss Contingency Trust, Contribution, Amended Proposal, Administrative and Litigation Costs		30,000,000
Liabilities Subject to Compromise, Asbestos Obligations		$ 367,500,000

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) € in Millions	Jan. 14, 2015	Nov. 30, 2016EUR (€)	Dec. 31, 2017USD ($)Potentially_Responsible_Partysitemi	Sep. 30, 2017USD ($)	Jun. 30, 2016USD ($)site	Mar. 31, 2016USD ($)	Jun. 30, 2014USD ($)	Sep. 30, 2017EUR (€)	Dec. 31, 2017USD ($)Potentially_Responsible_Partysitemi	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)mi	Dec. 31, 2017EUR (€)Potentially_Responsible_Partysitemi	Oct. 31, 2016USD ($)	Sep. 30, 2015site	Apr. 30, 2015USD ($)	Oct. 30, 2005
Site Contingency [Line Items]
Product Liability Contingency, Third Party Recovery				$ 15,000,000					$ 24,700,000
Accrual for Environmental Loss Contingencies			$ 27,300,000						27,300,000	$ 23,100,000
Accrual for Environmental Loss Contingencies, Provision for New Losses				1,900,000	$ 1,100,000				1,100,000
Investigative Sites Notice From The EPA | site					6
Lower Passaic River Study Area, Diamond Alkali Superfund Site, New Jersey [Abstract]
SiteContingency Remidial Investigation Feasibility Study Estimate Of Cost															$ 726,000,000
Site Contingency, Focused Feasibility Study, Estimate of Cost, Low End of Range													$ 165,000,000
Debt Instrument, Interest Rate, Stated Percentage																3.9375%
Asbestos settlement									$ 0	80,000,000	$ 0
Site Contingency, Number of Sites Subject to Remediation Activities, Total | site			15						15			15
Site Contingency, Sites Subject to Remediation Activities, Cost per Site, De Minimis Threshold									$ 100,000
Site Contingency, Number of Sites Subject to Remediation Activities, Investigation Completed | site			11						11			11
Site Contingency, Number of Sites Subject to Remediation Activities, Investigation in Progress | site			4						4			4
Accrual for Environmental Loss Contingencies, Component Amount				4,000,000
Lower Passaic River Study Area, Diamond Alkali Superfund Site, New Jersey [Member]
Lower Passaic River Study Area, Diamond Alkali Superfund Site, New Jersey [Abstract]
Site Contingency, Number of Potentially Responsible Parties, Cooperating | Potentially_Responsible_Party			70						70			70
Lower Passaic River Study Area, Focused Feasibility Study, April 11, 2014 [Member]
Site Contingency [Line Items]
Accrual for Environmental Loss Contingencies											$ 3,500,000
Onondaga Site EPA Remedial Investigation [Member]
Site Contingency [Line Items]
Accrual for Environmental Loss Contingencies, Provision for New Losses										1,500,000
Coltec Industries Inc. [Member]
Site Contingency [Line Items]
Accrual for Environmental Loss Contingencies			$ 3,800,000			$ 1,300,000			$ 3,800,000
Accrual for Environmental Loss Contingencies, Provision for New Losses			$ 3,500,000						$ 5,700,000
Minimum [Member]
Site Contingency [Line Items]
Site contingency, loss exposure in excess of accrual including portion allocated to counterparty, best estimate | €		€ 7.9
Site Contingency, Loss Exposure in Excess of Accrual, Best Estimate | €		1.8						€ 5.1
Lower Passaic River Study Area, Diamond Alkali Superfund Site, New Jersey [Abstract]
Portion Of Site Subject To Remediation | mi											8
Loss Contingency Accrual | €												€ 0.4
Minimum [Member] | Lower Passaic River Study Area, Focused Feasibility Study, April 11, 2014 [Member]
Site Contingency [Line Items]
Site Contingency, Loss Exposure in Excess of Accrual, Best Estimate						$ 1,380,000,000	$ 953,000,000
Maximum [Member]
Site Contingency [Line Items]
Site contingency, loss exposure in excess of accrual including portion allocated to counterparty, best estimate | €		10.2
Site Contingency, Loss Exposure in Excess of Accrual, Best Estimate		€ 2.1					$ 1,730,000,000	€ 6.6
Lower Passaic River Study Area, Diamond Alkali Superfund Site, New Jersey [Abstract]
Portion Of Site Subject To Remediation | mi			17						17		9	17
Crucible Steel Corporation [Member]
Site Contingency [Line Items]
Accrual for Environmental Loss Contingencies										$ 1,100,000
ARIZONA
Site Contingency [Line Items]
Investigative Sites Notice From The EPA | site														2
GST, LLC [Member]
Site Contingency [Line Items]
Loss Contingency, Insurance Coverage, Amount				$ 19,000,000
Lower Passaic River Study Area, Diamond Alkali Superfund Site, New Jersey [Abstract]
Liability For Asbestos and Environmental Claims, Period for Additional Contributions	7 years

Commitments and Contingencie113

Commitments and Contingencies - Additional Information (Detail) $ / shares in Units, € in Millions	Jan. 14, 2015USD ($)	May 29, 2014USD ($)	Dec. 31, 2017USD ($)mi	Sep. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Sep. 30, 2017EUR (€)	Sep. 30, 2016$ / shares	Dec. 31, 2017USD ($)mi	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)mi	Dec. 31, 2017EUR (€)mi	Nov. 11, 2016
Loss Contingencies [Line Items]
Loss contingency percentage of damages allocated to counterparty						35.00%
Insurance Policy Limit And Receivables Remaining Amount				$ 19,200,000
Accrual for Environmental Loss Contingencies, Charges to Expense for New Losses				1,900,000	$ 1,100,000			$ 1,100,000
Days After Effective Date Insurance Reimbursement Due						30 days
Insurance Policy Limit Remaining Amount			$ 14,200,000	18,800,000
Asbestos settlement								0	$ 80,000,000	$ 0
Option Indexed to Issuer's Equity, Strike Price | $ / shares							$ 1
Product Liability Contingency, Accrual, Discount Rate												4.50%
Loss contingency percentage of damages allocated to company						65.00%
Asbestos Issue [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded from Other Party				11,000,000
Loss Contingency, Insurance Coverage, Amount			44,400,000					44,400,000
Loss Contingency Insurance Coverage Amount Available Pending Future Claims			26,600,000					26,600,000
Loss Contingency, Receivable			29,400,000					29,400,000
GST, LLC [Member]
Loss Contingencies [Line Items]
Liabilities Subject to Compromise, Asbestos Obligations									$ 387,000,000	$ 337,500,000
Loss Contingency, Insurance Coverage, Amount				19,000,000
GST, LLC [Member] | Asbestos Issue [Member]
Loss Contingencies [Line Items]
Plan of Reorganization, Loss Contingency Trust, Contribution, Amended Proposal, Contingent Supplementary Contributions, Low Range of Possible Outcome	$ 1
Loss Contingency, Insurance Coverage, Amount Recovered, Insolvent Carrier			8,800,000					8,800,000
Loss Contingency, Insurance Coverage, Amount Recovered			152,300,000					152,300,000
Loss Contingency, Insurance Coverage, Amount Submitted for Reimbursement			17,800,000					17,800,000
Plan of Reorganization, Loss Contingency Trust, Contribution, Amended Proposal, Administrative and Litigation Costs		$ 220,000,000
Coltec Industries Inc. [Member] | Asbestos Issue [Member]
Loss Contingencies [Line Items]
Liabilities Subject to Compromise, Asbestos Obligations	367,500,000
Plan of Reorganization, Loss Contingency Trust, Contribution, Amended Proposal, Administrative and Litigation Costs	30,000,000
OldCo [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded from Other Party				$ 3,000,000		€ 6
Estimated Insurance Recoveries			$ 25,000,000					$ 25,000,000
Minimum [Member]
Loss Contingencies [Line Items]
Portion Of Site Subject To Remediation | mi										8
Loss Contingency Accrual | €											€ 0.4
Maximum [Member]
Loss Contingencies [Line Items]
Portion Of Site Subject To Remediation | mi			17					17		9	17
Future Claim Representative [Member] | GST, LLC [Member]
Loss Contingencies [Line Items]
Plan of Reorganization, Loss Contingency Trust, Contribution, Amended Proposal, Administrative and Litigation Costs	$ 30,000,000
New Coltec [Member]
Loss Contingencies [Line Items]
Option Indexed To Issuers Equity Settlement Alternatives Amount At Fair value			$ 20,000,000					$ 20,000,000
Percentage of Outstanding Voting Equity in GST LLC and GLMG								50.10%
Coltec Industries Inc. [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies, Charges to Expense for New Losses			$ 3,500,000					$ 5,700,000

Commitments and Contingencie114

Commitments and Contingencies - Schedule of Changes in Carrying Amount of Product Warranty Liability (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance at beginning of year	$ 5	$ 4.8	$ 3.5
Charges to expense	2.6	4.4	3.3
Settlements made (primarily payments)	(2.3)	(4.2)	(2)
Balance at end of period	$ 5.3	$ 5	$ 4.8

Commitments and Contingencie115

Commitments and Contingencies - Schedule of Future Insurance Proceeds (Detail) - Asbestos Issue [Member] $ in Millions	Dec. 31, 2017USD ($)
Loss Contingency, Estimated Insurance Recoveries [Abstract]
Loss Contingency, Estimated Insurance Recoveries, after Year Five	$ 15
Loss Contingency Accrual, Product Liability, Next Rolling Twelve Months	16.8
Loss Contingency, Estimated Insurance Recoveries, Year Two	5.9
Loss Contingency, Estimated Insurance Recoveries, Year Three	$ 2.5

Commitments and Contingencie116

Commitments and Contingencies - Schedule of Future Minimum Lease Payments (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
2,017	$ 12.3
2,018	10.6
2,019	9
2,020	6.8
2,021	5.3
Thereafter	5.4
Total minimum payments	49.4
Net rent expense	$ 12.2	$ 12.6	$ 14.3

Supplemental Guarantor Finan117

Supplemental Guarantor Financial Information Condensed Consolidating Statement of Operations (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Net sales	$ 362.5	$ 343.7	$ 307.6	$ 295.8	$ 286.9	$ 292.7	$ 313.2	$ 294.9	$ 1,309.6	$ 1,187.7	$ 1,204.4
Cost of sales									865.2	793	808.9
Gross profit	123.1	115.2	104.5	101.6	90.6	98.6	107.9	97.6	444.4	394.7	395.5
Operating expenses:
Selling, general and administrative									326.3	303.8	302.8
Goodwill and other Intangible Asset Impairment									10.1	0	47
Asbestos settlement									0	80	0
Other General Expense									16.9
Other									6.8	15.6	8.1
Total operating expenses									343.2	399.4	357.9
Operating income (loss)									101.2	(4.7)	37.6
Interest income (expense), net									(49.4)	(55.1)	(52.1)
Gain on reconsolidation of GST and OldCo									534.4	0	0
Other expense, net									(8.7)	(8.9)	(4.1)
Income (loss) before income taxes									577.5	(68.7)	(18.6)
Income tax benefit (expense)									(37.7)	28.6	(2.3)
Income (loss) before equity in earnings of subsidiaries									539.8	(40.1)	(20.9)
Equity in earnings of subsidiaries, net of tax									0	0	0
Net income (loss)	$ 34.2	$ 490.2	$ 9	$ 6.4	$ (2.9)	$ 6	$ 3.6	$ (46.8)	539.8	(40.1)	(20.9)
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net sales									(109.6)	(81)	(61.5)
Cost of sales									(109.6)	(81)	(61.5)
Gross profit									0	0	0
Operating expenses:
Selling, general and administrative									0	0	0
Other General Expense									0
Other										0	0
Total operating expenses									0	0	0
Operating income (loss)									0	0	0
Interest income (expense), net									0	0	0
Other expense, net									0	0	0
Income (loss) before income taxes									0	0	0
Income tax benefit (expense)									0	0	0
Income (loss) before equity in earnings of subsidiaries									0	0	0
Equity in earnings of subsidiaries, net of tax									(600.5)	(10.2)	8.1
Net income (loss)									(600.5)	(10.2)	8.1
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Net sales									0	0	0
Cost of sales									0	0	0
Gross profit									0	0	0
Operating expenses:
Selling, general and administrative									33.1	27.7	27.6
Other General Expense									1.1
Other										4.8	1.8
Total operating expenses									34.2	32.5	29.4
Operating income (loss)									(34.2)	(32.5)	(29.4)
Interest income (expense), net									(25.4)	(18.5)	(13.1)
Other expense, net									0	0	(2.8)
Income (loss) before income taxes									(59.6)	(51)	(45.3)
Income tax benefit (expense)									17.6	17.6	12.1
Income (loss) before equity in earnings of subsidiaries									(42)	(33.4)	(33.2)
Equity in earnings of subsidiaries, net of tax									581.8	(6.7)	12.3
Net income (loss)									539.8	(40.1)	(20.9)
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net sales									921.9	829	837.8
Cost of sales									644.6	582.4	591.6
Gross profit									277.3	246.6	246.2
Operating expenses:
Selling, general and administrative									183	164	157.1
Goodwill and other Intangible Asset Impairment											5.6
Asbestos settlement										80
Other General Expense									12.1
Other										3.3	1.2
Total operating expenses									195.1	247.3	163.9
Operating income (loss)									82.2	(0.7)	82.3
Interest income (expense), net									(24.1)	(36.2)	(38.8)
Gain on reconsolidation of GST and OldCo									534.4
Other expense, net									(8.7)	(8.4)	(1.3)
Income (loss) before income taxes									583.8	(45.3)	42.2
Income tax benefit (expense)									(20.7)	21.7	(9.5)
Income (loss) before equity in earnings of subsidiaries									563.1	(23.6)	32.7
Equity in earnings of subsidiaries, net of tax									18.7	16.9	(20.4)
Net income (loss)									581.8	(6.7)	12.3
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net sales									497.3	439.7	428.1
Cost of sales									330.2	291.6	278.8
Gross profit									167.1	148.1	149.3
Operating expenses:
Selling, general and administrative									110.2	112.1	118.1
Goodwill and other Intangible Asset Impairment											41.4
Other General Expense									3.7
Other										7.5	5.1
Total operating expenses									113.9	119.6	164.6
Operating income (loss)									53.2	28.5	(15.3)
Interest income (expense), net									0.1	(0.4)	(0.2)
Other expense, net									0	(0.5)	0
Income (loss) before income taxes									53.3	27.6	(15.5)
Income tax benefit (expense)									(34.6)	(10.7)	(4.9)
Income (loss) before equity in earnings of subsidiaries									18.7	16.9	(20.4)
Equity in earnings of subsidiaries, net of tax									0	0	0
Net income (loss)									$ 18.7	$ 16.9	$ (20.4)

Supplemental Guarantor Finan118

Supplemental Guarantor Financial Information Condensed Consolidating Statements of Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Statement of Income Captions [Line Items]
Net income (loss)	$ 34.2	$ 490.2	$ 9	$ 6.4	$ (2.9)	$ 6	$ 3.6	$ (46.8)	$ 539.8	$ (40.1)	$ (20.9)
Other comprehensive income (loss):
Foreign currency translation adjustments									14.4	(16.3)	(21.9)
Pension and post-retirement benefits adjustment (excluding amortization)									5.2	(7.8)	(3.4)
Amortization of pension and post-retirement benefits included in net income (loss)									7.7	6.9	7.1
Other comprehensive income (loss), before tax									27.3	(17.2)	(18.2)
Income tax benefit (expense) related to items of other comprehensive income (loss)									(4.8)	0.4	(1.8)
Other comprehensive income (loss), net of tax									22.5	(16.8)	(20)
Comprehensive income (loss)									562.3	(56.9)	(40.9)
Eliminations [Member]
Condensed Statement of Income Captions [Line Items]
Net income (loss)									(600.5)	(10.2)	8.1
Other comprehensive income (loss):
Foreign currency translation adjustments									(28.8)	32.6	43.8
Pension and post-retirement benefits adjustment (excluding amortization)									(6.5)	7.7	3.1
Amortization of pension and post-retirement benefits included in net income (loss)									(7.8)	(6.8)	(7.3)
Other comprehensive income (loss), before tax									(43.1)	33.5	39.6
Income tax benefit (expense) related to items of other comprehensive income (loss)									5.2	(0.3)	1.9
Other comprehensive income (loss), net of tax									(37.9)	33.2	41.5
Comprehensive income (loss)									(638.4)	23	49.6
Parent [Member]
Condensed Statement of Income Captions [Line Items]
Net income (loss)									539.8	(40.1)	(20.9)
Other comprehensive income (loss):
Foreign currency translation adjustments									14.4	(16.3)	(21.9)
Pension and post-retirement benefits adjustment (excluding amortization)									5.2	(7.8)	(3.4)
Amortization of pension and post-retirement benefits included in net income (loss)									7.7	6.9	7.1
Other comprehensive income (loss), before tax									27.3	(17.2)	(18.2)
Income tax benefit (expense) related to items of other comprehensive income (loss)									(4.8)	0.4	(1.8)
Other comprehensive income (loss), net of tax									22.5	(16.8)	(20)
Comprehensive income (loss)									562.3	(56.9)	(40.9)
Guarantor Subsidiaries [Member]
Condensed Statement of Income Captions [Line Items]
Net income (loss)									581.8	(6.7)	12.3
Other comprehensive income (loss):
Foreign currency translation adjustments									14.4	(16.3)	(21.9)
Pension and post-retirement benefits adjustment (excluding amortization)									5.2	(8.3)	(3.6)
Amortization of pension and post-retirement benefits included in net income (loss)									7.7	6.6	7.1
Other comprehensive income (loss), before tax									27.3	(18)	(18.4)
Income tax benefit (expense) related to items of other comprehensive income (loss)									(4.8)	0.5	(1.7)
Other comprehensive income (loss), net of tax									22.5	(17.5)	(20.1)
Comprehensive income (loss)									604.3	(24.2)	(7.8)
Non-Guarantor Subsidiaries [Member]
Condensed Statement of Income Captions [Line Items]
Net income (loss)									18.7	16.9	(20.4)
Other comprehensive income (loss):
Foreign currency translation adjustments									14.4	(16.3)	(21.9)
Pension and post-retirement benefits adjustment (excluding amortization)									1.3	0.6	0.5
Amortization of pension and post-retirement benefits included in net income (loss)									0.1	0.2	0.2
Other comprehensive income (loss), before tax									15.8	(15.5)	(21.2)
Income tax benefit (expense) related to items of other comprehensive income (loss)									(0.4)	(0.2)	(0.2)
Other comprehensive income (loss), net of tax									15.4	(15.7)	(21.4)
Comprehensive income (loss)									$ 34.1	$ 1.2	$ (41.8)

Supplemental Guarantor Finan119

Supplemental Guarantor Financial Information Condensed Consolidating Statement of Cash Flows (Details) - USD ($) $ in Millions	Apr. 30, 2016	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Net cash flows from operating activities				$ 46.6	$ 64.5	$ 86.5
INVESTING ACTIVITIES
Purchases of property, plant and equipment				(41)	(35.8)	(36.8)
Payments for capitalized internal-use software				(3.7)	(4.1)	(4.6)
Proceeds from sale of business				0	6.6	0
Payments for acquisitions, net of cash acquired	$ (22.6)		$ (44.6)	(44.6)	(28.5)	(45.5)
Cash Acquired from Acquisition				(41.1)	0	0
Payments to Acquire Interest in Subsidiaries and Affiliates				(4.8)	0	0
Payments to Acquire Other Investments				(45.2)	0	0
Other				0.5	0.4	0.4
Net cash used in investing activities				(97.7)	(61.4)	(86.5)
FINANCING ACTIVITIES
Net payments between subsidiaries				0	0	0
Intercompany dividends				0	0	0
Proceeds from debt				635.7	350.8	230.8
Repayments of debt				(484.3)	(278.1)	(189)
Repurchase of common stock		$ (5.3)		(11.5)	(30.4)	(85.3)
Payments of Ordinary Dividends, Common Stock				(19)	(18.1)	(18)
Dividends paid				(19)	(18.1)
Repurchase of convertible debentures conversion option				0	0	(21.6)
Other				(2.4)	(2.2)	(2.1)
Net cash provided by (used in) financing activities				118.5	22	(85.2)
Effect of Exchange Rate on Cash and Cash Equivalents				10.4	(17)	(5.6)
Net increase (decrease) in cash and cash equivalents				77.8	8.1	(90.8)
Cash and cash equivalents at beginning of year				111.5	103.4	194.2
Cash and cash equivalents at end of year		189.3		189.3	111.5	103.4
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash flows from operating activities				(0.1)	(12.2)	(0.5)
INVESTING ACTIVITIES
Purchases of property, plant and equipment				0	0	0
Payments for capitalized internal-use software				0	0	0
Proceeds from sale of business					0
Payments for acquisitions, net of cash acquired				0	0	0
Other				0	0	0
Net cash used in investing activities				0	0	0
FINANCING ACTIVITIES
Net payments between subsidiaries				0	0	0
Intercompany dividends				0.1	12.2	0.5
Proceeds from debt				0	0	0
Repayments of debt				0	0	0
Repurchase of common stock				0	0
Dividends paid				0	0
Repurchase of convertible debentures conversion option						0
Other				0	0	0
Net cash provided by (used in) financing activities				0.1	12.2	0.5
Effect of Exchange Rate on Cash and Cash Equivalents				0	0	0
Net increase (decrease) in cash and cash equivalents				0	0	0
Cash and cash equivalents at beginning of year				0	0	0
Cash and cash equivalents at end of year		0		0	0	0
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash flows from operating activities				(106.5)	(45.9)	(25.6)
INVESTING ACTIVITIES
Purchases of property, plant and equipment				0	0	0
Payments for capitalized internal-use software				0	0	0
Proceeds from sale of business					0
Payments for acquisitions, net of cash acquired				0	0	0
Other				0	0	0
Net cash used in investing activities				0	0	0
FINANCING ACTIVITIES
Net payments between subsidiaries				(12.1)	96.6	178.1
Intercompany dividends				0	0	0
Proceeds from debt				151.5	0	0
Repayments of debt				0	0	(25.5)
Repurchase of common stock				(11.5)	(30.4)	(85.3)
Payments of Ordinary Dividends, Common Stock						(18)
Dividends paid				(19)	(18.1)
Repurchase of convertible debentures conversion option						(21.6)
Other				(2.4)	(2.2)	(2.1)
Net cash provided by (used in) financing activities				106.5	45.9	25.6
Effect of Exchange Rate on Cash and Cash Equivalents				0	0	0
Net increase (decrease) in cash and cash equivalents				0	0	0
Cash and cash equivalents at beginning of year				0	0	0
Cash and cash equivalents at end of year		0		0	0	0
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash flows from operating activities				61.9	82.9	77.5
INVESTING ACTIVITIES
Purchases of property, plant and equipment				(28.2)	(28.4)	(23)
Payments for capitalized internal-use software				(3.6)	(3.8)	(4.6)
Proceeds from sale of business					2.9
Payments for acquisitions, net of cash acquired				(39.5)	(25.5)	(42.4)
Cash Acquired from Acquisition				41.1
Payments to Acquire Interest in Subsidiaries and Affiliates				(4.8)
Payments to Acquire Other Investments				(45.2)
Other				0	0	0.1
Net cash used in investing activities				(80.2)	(54.8)	(69.9)
FINANCING ACTIVITIES
Net payments between subsidiaries				19.3	(95.6)	(183.9)
Intercompany dividends				0	0	0
Proceeds from debt				480.7	344.7	225
Repayments of debt				(482.5)	(277.1)	(162.9)
Repurchase of common stock				0	0
Dividends paid				0	0
Repurchase of convertible debentures conversion option						0
Other				0	0	0
Net cash provided by (used in) financing activities				17.5	(28)	(121.8)
Effect of Exchange Rate on Cash and Cash Equivalents				0	0	0
Net increase (decrease) in cash and cash equivalents				(0.8)	0.1	(114.2)
Cash and cash equivalents at beginning of year				0.8	0.7	114.9
Cash and cash equivalents at end of year		0		0	0.8	0.7
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash flows from operating activities				91.3	39.7	35.1
INVESTING ACTIVITIES
Purchases of property, plant and equipment				(12.8)	(7.4)	(13.8)
Payments for capitalized internal-use software				(0.1)	(0.3)	0
Proceeds from sale of business					3.7
Payments for acquisitions, net of cash acquired				(5.1)	(3)	(3.1)
Other				0.5	0.4	0.3
Net cash used in investing activities				(17.5)	(6.6)	(16.6)
FINANCING ACTIVITIES
Net payments between subsidiaries				(7.2)	(1)	5.8
Intercompany dividends				(0.1)	(12.2)	(0.5)
Proceeds from debt				3.5	6.1	5.8
Repayments of debt				(1.8)	(1)	(0.6)
Repurchase of common stock				0	0
Dividends paid				0	0
Repurchase of convertible debentures conversion option						0
Other				0	0	0
Net cash provided by (used in) financing activities				(5.6)	(8.1)	10.5
Effect of Exchange Rate on Cash and Cash Equivalents				10.4	(17)	(5.6)
Net increase (decrease) in cash and cash equivalents				78.6	8	23.4
Cash and cash equivalents at beginning of year				110.7	102.7	79.3
Cash and cash equivalents at end of year		$ 189.3		$ 189.3	$ 110.7	$ 102.7

Supplemental Guarantor Finan120

Supplemental Guarantor Financial Information Condensed Consolidating Balance Sheets (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 189.3	$ 111.5	$ 103.4	$ 194.2
Accounts receivable, net	261.7	208.1
Intercompany receivables	0	0
Inventories	204.1	175.4
Income Tax Receivable	113.2	6.5
Prepaid expenses and other current assets	51.3	23.4
Prepaid expenses and other current assets		29.9
Total current assets	819.6	524.9
Property, plant and equipment, net	296.9	215.4
Goodwill	336.1	201.5	195.9
Other intangible assets, net	347	176.9
Investment in GST	0	236.9
Intercompany receivables	0	0
Investment in subsidiaries	0	0
Other assets	86.5	190.8
Total assets	1,886.1	1,546.4
Current liabilities
Short-term borrowings from GST	0	26.2
Notes payable to GST	0	12.7
Current maturities of long-term debt	0.2	0.2
Accounts payable	130.7	102.9
Intercompany payables	0	0
Other Liabilities, Current	137.2	161
Total current liabilities	268.1	303
Long-term debt	618.3	424.8
Notes payable to GST	0	283.2
Intercompany payables	0	0
Liabilities, Other than Long-term Debt, Noncurrent	96.9	176.9
Total liabilities	983.3	1,187.9
Total shareholders’ equity	902.8	358.5	459.8	623.8
Total liabilities and equity	1,886.1	1,546.4
Eliminations [Member]
Current assets
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0
Intercompany receivables	(30.7)	(14.9)
Inventories	0	0
Income Tax Receivable	(22.4)
Prepaid expenses and other current assets	0
Prepaid expenses and other current assets		(17.7)
Total current assets	(53.1)	(32.6)
Property, plant and equipment, net	0	0
Goodwill	0	0
Other intangible assets, net	0	0
Investment in GST		0
Intercompany receivables	(22.9)	(45.1)
Investment in subsidiaries	(1,721.4)	(917.5)
Other assets	0	0
Total assets	(1,797.4)	(995.2)
Current liabilities
Short-term borrowings from GST		0
Notes payable to GST		0
Current maturities of long-term debt	0	0
Accounts payable	0	0
Intercompany payables	(30.7)	(14.9)
Other Liabilities, Current	(22.4)	(17.7)
Total current liabilities	(53.1)	(32.6)
Long-term debt	0	0
Notes payable to GST		0
Intercompany payables	(22.9)	(45.1)
Liabilities, Other than Long-term Debt, Noncurrent	0	0
Total liabilities	(76)	(77.7)
Total shareholders’ equity	(1,721.4)	(917.5)
Total liabilities and equity	(1,797.4)	(995.2)
Parent [Member]
Current assets
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0.2
Intercompany receivables	0	0
Inventories	0	0
Income Tax Receivable	132.3
Prepaid expenses and other current assets	4.3
Prepaid expenses and other current assets		21.3
Total current assets	136.6	21.5
Property, plant and equipment, net	0	0.1
Goodwill	0	0
Other intangible assets, net	0	0
Investment in GST		0
Intercompany receivables	0	0
Investment in subsidiaries	1,261.3	681.1
Other assets	12.8	16.4
Total assets	1,410.7	719.1
Current liabilities
Short-term borrowings from GST		0
Notes payable to GST		0
Current maturities of long-term debt	0	0
Accounts payable	2.3	2.3
Intercompany payables	0	0
Other Liabilities, Current	22.8	15.3
Total current liabilities	25.1	17.6
Long-term debt	444.2	294.1
Notes payable to GST		0
Intercompany payables	22.9	35
Liabilities, Other than Long-term Debt, Noncurrent	15.7	13.9
Total liabilities	507.9	360.6
Total shareholders’ equity	902.8	358.5
Total liabilities and equity	1,410.7	719.1
Guarantor Subsidiaries [Member]
Current assets
Cash and cash equivalents	0	0.8	0.7	114.9
Accounts receivable, net	180.1	151.2
Intercompany receivables	24	10.2
Inventories	135.4	125.9
Income Tax Receivable	1.3
Prepaid expenses and other current assets	26.5
Prepaid expenses and other current assets		8.9
Total current assets	367.3	297
Property, plant and equipment, net	206.8	148.5
Goodwill	261	175.5
Other intangible assets, net	284.2	156.5
Investment in GST		236.9
Intercompany receivables	22.9	43.6
Investment in subsidiaries	460.1	236.4
Other assets	59.3	156.2
Total assets	1,661.6	1,450.6
Current liabilities
Short-term borrowings from GST		0
Notes payable to GST		12.7
Current maturities of long-term debt	0.2	0.2
Accounts payable	82.5	61.9
Intercompany payables	6.7	4.7
Other Liabilities, Current	90.1	130.1
Total current liabilities	179.5	209.6
Long-term debt	174.1	130.7
Notes payable to GST		283.2
Intercompany payables	0	1.4
Liabilities, Other than Long-term Debt, Noncurrent	46.7	144.6
Total liabilities	400.3	769.5
Total shareholders’ equity	1,261.3	681.1
Total liabilities and equity	1,661.6	1,450.6
Non-Guarantor Subsidiaries [Member]
Current assets
Cash and cash equivalents	189.3	110.7	$ 102.7	$ 79.3
Accounts receivable, net	81.6	56.7
Intercompany receivables	6.7	4.7
Inventories	68.7	49.5
Income Tax Receivable	2
Prepaid expenses and other current assets	20.5
Prepaid expenses and other current assets		17.4
Total current assets	368.8	239
Property, plant and equipment, net	90.1	66.8
Goodwill	75.1	26
Other intangible assets, net	62.8	20.4
Investment in GST		0
Intercompany receivables	0	1.5
Investment in subsidiaries	0	0
Other assets	14.4	18.2
Total assets	611.2	371.9
Current liabilities
Short-term borrowings from GST		26.2
Notes payable to GST		0
Current maturities of long-term debt	0	0
Accounts payable	45.9	38.7
Intercompany payables	24	10.2
Other Liabilities, Current	46.7	33.3
Total current liabilities	116.6	108.4
Long-term debt	0	0
Notes payable to GST		0
Intercompany payables	0	8.7
Liabilities, Other than Long-term Debt, Noncurrent	34.5	18.4
Total liabilities	151.1	135.5
Total shareholders’ equity	460.1	236.4
Total liabilities and equity	$ 611.2	$ 371.9

Supplemental Guarantor Finan121

Supplemental Guarantor Financial Information Supplemental Guarantor Financial information - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2017
Condensed Financial Statements, Captions [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent		100.00%
Adoption of share-based payment accounting standard	$ (0.3)	$ 0.2

Selected Quarterly Financial122

Selected Quarterly Financial Data - Schedule of Selected Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Selected Quarterly Financial Information [Abstract]
Net sales	$ 362.5	$ 343.7	$ 307.6	$ 295.8	$ 286.9	$ 292.7	$ 313.2	$ 294.9	$ 1,309.6	$ 1,187.7	$ 1,204.4
Gross profit	123.1	115.2	104.5	101.6	90.6	98.6	107.9	97.6	444.4	394.7	395.5
Net income (loss)	$ 34.2	$ 490.2	$ 9	$ 6.4	$ (2.9)	$ 6	$ 3.6	$ (46.8)	$ 539.8	$ (40.1)	$ (20.9)
Basic earnings (loss) per share	$ 1.60	$ 22.98	$ 0.42	$ 0.30	$ (0.14)	$ 0.28	$ 0.17	$ (2.15)	$ 25.28	$ (1.86)	$ (0.93)
Diluted earnings (loss) per share	$ 1.57	$ 22.49	$ 0.41	$ 0.30	$ (0.14)	$ 0.28	$ 0.17	$ (2.15)	$ 24.76	$ (1.86)	$ (0.93)
Asbestos settlement									$ 0	$ 80	$ 0
Gain on reconsolidation of GST and OldCo									$ 534.4	$ 0	$ 0

Schedule II - Valuation and 123

Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance, Beginning of Year	$ 4.9	$ 5.4	$ 7
Charge (Credit) to Expense	1.2	1.1	(0.2)
Write-off of Receivables/Expiration of Net Operating Losses	(1.6)	(1.6)	(1.4)
Other	0.2	0	0
Balance, End of Year	4.7	4.9	5.4
Deferred Income Tax Valuation Allowance [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance, Beginning of Year	20.2	17.6	19.9
Charge (Credit) to Expense	1.2	4.6	0.4
Write-off of Receivables/Expiration of Net Operating Losses	(0.1)	(0.1)	(0.1)
Other	4.4	(1.9)	(2.6)
Balance, End of Year	$ 25.7	$ 20.2	$ 17.6