Mistras (MG) 10-Q 9 Nov 17 2017 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Nov. 02, 2017
Document and Entity Information
Entity Registrant Name	Mistras Group, Inc.
Entity Central Index Key	1,436,126
Document Type	10-Q
Document Period End Date	Sep. 30, 2017
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		28,290,709
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current Assets
Cash and cash equivalents	$ 26,863	$ 19,154
Accounts receivable, net	140,189	130,852
Inventories	11,237	10,017
Deferred income taxes	0	6,230
Prepaid expenses and other current assets	16,077	16,399
Total current assets	194,366	182,652
Property, plant and equipment, net	77,173	73,149
Intangible assets, net	42,242	40,007
Goodwill	165,704	169,940
Deferred income taxes	2,108	1,086
Other assets	2,829	2,593
Total assets	484,422	469,427
Current Liabilities
Accounts payable	8,925	6,805
Accrued expenses and other current liabilities	65,608	58,697
Current portion of long-term debt	2,490	1,379
Current portion of capital lease obligations	6,261	6,488
Income taxes payable	4,576	4,342
Total current liabilities	87,860	77,711
Long-term debt, net of current portion	101,803	85,917
Obligations under capital leases, net of current portion	8,349	9,682
Deferred income taxes	9,238	17,584
Other long-term liabilities	9,510	7,789
Total liabilities	216,760	198,683
Commitments and contingencies
Equity
Preferred stock, 10,000,000 shares authorized	0	0
Common stock, $0.01 par value, 200,000,000 shares authorized, 29,434,816 and 29,216,745 shares issued	294	292
Additional paid-in capital	221,149	217,211
Treasury stock, at cost, 1,146,249 and 420,258 shares	(24,923)	(9,000)
Retained earnings	88,744	91,803
Accumulated other comprehensive loss	(17,789)	(29,724)
Total Mistras Group, Inc. stockholders’ equity	267,475	270,582
Non-controlling interests	187	162
Total equity	267,662	270,744
Total liabilities and equity	$ 484,422	$ 469,427

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	29,434,816	29,216,745
Treasury stock (in shares)	1,146,249	420,258

Unaudited Condensed Consolidate

Unaudited Condensed Consolidated Statements of Income (Loss) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Statement [Abstract]
Revenue	$ 179,570	$ 168,811	$ 513,326	$ 514,606
Cost of revenue	126,316	112,754	360,144	352,027
Depreciation	5,357	5,406	15,790	16,423
Gross profit	47,897	50,651	137,392	146,156
Selling, general and administrative expenses	38,217	34,995	113,491	107,266
Impairment charges	15,810	0	15,810	0
Research and engineering	555	643	1,749	1,928
Depreciation and amortization	2,738	2,513	7,854	8,140
Litigation charges	1,200	0	1,200	6,320
Acquisition-related expense (benefit), net	(248)	384	(589)	(99)
Income (loss) from operations	(10,375)	12,116	(2,123)	22,601
Interest expense	1,081	778	3,114	2,218
Income (loss) before (benefit) provision for income taxes	(11,456)	11,338	(5,237)	20,383
(Benefit) provision for income taxes	(4,503)	4,083	(2,199)	6,908
Net income (loss)	(6,953)	7,255	(3,038)	13,475
Less: net income attributable to non-controlling interests, net of taxes	15	17	21	29
Net income (loss) attributable to Mistras Group, Inc.	$ (6,968)	$ 7,238	$ (3,059)	$ 13,446
Earnings (loss) per common share:
Basic (in dollars per share)	$ (0.25)	$ 0.25	$ (0.11)	$ 0.46
Diluted (in dollars per share)	$ (0.25)	$ 0.24	$ (0.11)	$ 0.45
Weighted average common shares outstanding:
Basic (in shares)	28,274	29,051	28,465	28,966
Diluted (in shares)	28,274	30,231	28,465	30,139

Unaudited Condensed Consolidat5

Unaudited Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (6,953)	$ 7,255	$ (3,038)	$ 13,475
Other comprehensive income:
Foreign currency translation adjustments	4,443	(2,641)	11,935	1,966
Comprehensive income (loss)	(2,510)	4,614	8,897	15,441
Less: comprehensive income attributable to non-controlling interest	16	13	25	25
Comprehensive income (loss) attributable to Mistras Group, Inc.	$ (2,526)	$ 4,601	$ 8,872	$ 15,416

Unaudited Condensed Consolidat6

Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Cash flows from operating activities
Net income (loss)	$ (3,038)	$ 13,475
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation and amortization	23,644	24,563
Impairment charges	15,810	0
Deferred income taxes	(4,755)	512
Share-based compensation expense	5,179	5,161
Bad debt provision for unexpected customer bankruptcy	1,200	0
Fair value adjustments to contingent consideration	(880)	(582)
Other	226	(2,017)
Changes in operating assets and liabilities, net of effect of acquisitions
Accounts receivable	(4,017)	9,968
Inventories	(838)	200
Prepaid expenses and other assets	995	(2,777)
Accounts payable	1,466	(1,761)
Accrued expenses and other liabilities	668	5,247
Income taxes payable	(434)	120
Net cash provided by operating activities	35,226	52,109
Cash flows from investing activities
Purchase of property, plant and equipment	(14,413)	(11,238)
Purchase of intangible assets	(941)	(1,106)
Acquisition of businesses, net of cash acquired	(8,356)	(1,200)
Proceeds from sale of equipment	1,194	1,057
Net cash used in investing activities	(22,516)	(12,487)
Cash flows from financing activities
Repayment of capital lease obligations	(4,878)	(6,703)
Proceeds from borrowings of long-term debt	5,599	761
Repayment of long-term debt	(1,638)	(12,187)
Proceeds from revolver	38,400	38,200
Repayment of revolver	(26,900)	(49,000)
Payment of contingent consideration for business acquisitions	(554)	(2,919)
Purchases of treasury stock	(15,923)	0
Taxes paid related to net share settlement of share-based awards	(1,497)	(2,146)
Excess tax benefit from share-based compensation	0	646
Proceeds from exercise of stock options	277	857
Net cash used in financing activities	(7,114)	(32,491)
Effect of exchange rate changes on cash and cash equivalents	2,113	(221)
Net change in cash and cash equivalents	7,709	6,910
Cash and cash equivalents
Beginning of period	19,154	9,599
End of period	26,863	16,509
Supplemental disclosure of cash paid
Interest	3,031	2,454
Income taxes	2,868	9,562
Noncash investing and financing
Equipment acquired through capital lease obligations	2,824	7,408
Issuance of notes payable and other debt obligations, primarily related to acquisitions	$ 0	$ 325

Description of Business and Bas

Description of Business and Basis of Presentation	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Basis of Presentation	Description of Business and Basis of Presentation Description of Business Mistras Group, Inc. and subsidiaries ("the Company") is a leading “one source” global provider of technology-enabled asset protection solutions used to evaluate the structural integrity and reliability of critical energy, industrial and public infrastructure. The Company combines industry-leading products and technologies, expertise in mechanical integrity (MI), non-destructive testing (NDT) and mechanical services and proprietary data analysis software to deliver a comprehensive portfolio of customized solutions, ranging from routine inspections to complex, plant-wide asset integrity assessments and management. These mission critical solutions enhance customers’ ability to extend the useful life of their assets, increase productivity, minimize repair costs, comply with governmental safety and environmental regulations, manage risk and avoid catastrophic disasters. The Company serves a global customer base of companies with asset-intensive infrastructure, including companies in the oil and gas, fossil and nuclear power, alternative and renewable energy, public infrastructure, chemicals, commercial aerospace and defense, transportation, primary metals and metalworking, pharmaceutical/biotechnology and food processing industries and research and engineering institutions. Basis of Presentation The condensed consolidated financial statements contained in this report are unaudited. In the opinion of management, the condensed consolidated financial statements include all adjustments, which are of a normal recurring nature, necessary for a fair presentation of the results for the interim periods of the fiscal years ending December 31, 2017 and 2016 . Certain items included in these statements are based on management’s estimates. Actual results may differ from those estimates. The results of operations for any interim period are not necessarily indicative of the results expected for the year. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the notes to the audited consolidated financial statements contained in the Company’s Transition Report on Form 10-K (“2016 Transition Report”) for the transition period ended December 31, 2016 , as filed with the Securities and Exchange Commission on March 20, 2017 . Principles of Consolidation The accompanying unaudited condensed consolidated financial statements include the accounts of Mistras Group, Inc. and its wholly and majority-owned subsidiaries. For subsidiaries in which the Company’s ownership interest is less than 100%, the non-controlling interests are reported in stockholders’ equity in the accompanying condensed consolidated balance sheets. The non-controlling interests in net income, net of tax, is classified separately in the accompanying condensed consolidated statements of income. All significant intercompany accounts and transactions have been eliminated in consolidation. On January 3, 2017, the Company's Board of Directors approved a change in the Company's fiscal year end from May 31 to December 31, effective December 31, 2016. The transition period was for the seven months ended December 31, 2016 ("the transition period"). Prior to this change, the Company's International segment was consolidated on a one month lag. Therefore, for this interim report, the condensed consolidated income statements include a one month lag for the International segment for the three and nine months ended September 30, 2016. Management does not believe that any events occurred during the one-month lag period that would have a material effect on the Company’s condensed consolidated financial statements. The one - month lag was removed with the change in the Company's fiscal year noted above, and accordingly, the condensed consolidated income statements do not include a one month lag for the International segment's results for the three and nine months ended September 30, 2017. Reclassification Certain amounts in prior periods have been reclassified to conform to the current year presentation. Such reclassifications did not have a material effect on the Company's financial condition or results of operations as previously reported. Customers One customer, primarily generated from the Services segment, accounted for approximately 10% and 11% of our revenues for the three and nine months ended September 30, 2017 . This customer accounted for 8% of accounts receivable as of September 30, 2017. One customer accounted for 14% and 12% of our revenues for the three and nine months ended September 30, 2016 . Significant Accounting Policies The Company’s significant accounting policies are disclosed in Note 2 — Summary of Significant Accounting Policies in the Company's 2016 Transition Report. On an ongoing basis, the Company evaluates its estimates and assumptions, including among other things, those related to revenue recognition, valuations of accounts receivable, long-lived assets, goodwill, deferred tax assets and uncertain tax positions. Since the date of the 2016 Transition Report, there have been no material changes to the Company's significant accounting policies. Recent Accounting Pronouncements In August 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date, which defers the effective date of ASU 2014-09 for all entities by one year. This update is effective for public business entities for annual reporting periods beginning after December 15, 2017, including interim periods within those reporting periods. Earlier application is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. ASU 2014-09 will become effective for us beginning 2018, which is when we plan to adopt this standard. The ASU permits two methods of adoption: retrospectively to each prior reporting period presented (full retrospective method), or retrospectively with the cumulative effect of initially applying the guidance recognized at the date of initial application (the cumulative catch-up transition method). The ASU also requires expanded disclosures relating to the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. Additionally, qualitative and quantitative disclosures are required about customer contracts, significant judgments and changes in judgments, and assets recognized from the costs to obtain or fulfill a contract. The Company plans to adopt this guidance using the cumulative catch-up method. We are still in the process of evaluating the effect of adoption on our condensed consolidated financial statements and are currently assessing our contracts with customers across each of its global operating segments. Our assessment is not yet complete and therefore we are unable to quantify the potential impacts. However, as most of our projects are short-term in nature and billed on at time and materials basis, we do not currently anticipate that the adoption of ASU 2014-09 will result in substantial changes to the overall pattern or timing of our revenue recognition. In November 2015, the FASB issued ASU No. 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes. This amendment will simplify the presentation of deferred tax assets and liabilities on the balance sheet and require all deferred tax assets and liabilities to be treated as non-current. ASU 2015-17 is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2016, with early adoption permitted. The Company adopted this guidance prospectively beginning in the first quarter of 2017, which did not have a material impact on the condensed consolidated financial statements and related disclosures. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842). This amendment supersedes previous accounting guidance ( Topic 840) and requires all leases, with the exception of leases with a term of 12 months or less, to be recorded on the balance sheet as lease assets and lease liabilities. ASU 2016-02 is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2018, with early adoption permitted. The standard requires lessees and lessors to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. The Company is evaluating the effect that ASU 2016-02 will have on its condensed consolidated financial statements and related disclosures. In March 2016, the FASB issued ASU No. 2016-09, Stock Compensation (Topic 718). This amendment simplifies certain aspects of accounting for share-based payment transactions, which include accounting for income taxes and the related impact on the statement of cash flows, an option to account for forfeitures when they occur in addition to the existing guidance to estimate the forfeitures of awards, classification of awards as either equity or liabilities and classification on the statement of cash flows for employee taxes paid to tax authorities on shares withheld for vesting. ASU 2016-09 is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2016, with early adoption permitted. The Company adopted this guidance prospectively beginning in the first quarter of 2017, and accordingly, is recording excess tax benefits and tax deficiencies as a component of income tax expense. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230). This amendment will provide guidance on the presentation and classification of specific cash flow items to improve consistency within the statement of cash flows. ASU 2016-15 is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2017, with early adoption permitted. The Company is evaluating the impact that ASU 2016-15 will have on its condensed consolidated financial statements and related disclosures. In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230). This amendment will clarify the presentation of restricted cash on the statement of cash flows. Amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning and ending cash balances on the statement of cash flows. ASU 2016-18 is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2017, with early adoption permitted. The Company does not expect that ASU 2016-18 will have a material impact on its condensed consolidated financial statements and related disclosures. In January 2017, the FASB issued ASU No. 2017-04, Intangibles-Goodwill and Other (Topic 350). This amendment eliminates Step Two of the goodwill impairment test. Under the amendments in this update, entities should perform the annual goodwill impairment test by comparing the carrying value of its reporting units to their fair value. An entity should record an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value. Tax deductibility of goodwill should be considered in evaluating any reporting unit's impairment loss to be taken. ASU 2017-04 is effective for fiscal years beginning after December 15, 2019, with early adoption permitted. The Company has early adopted ASU 2017-04 in the third quarter of 2017 for its condensed consolidated financial statements and related disclosures. See Notes 7 and 8 for information on the impairment of assets in the Products and Systems reporting unit during the three months ended September 30, 2017. In May 2017, the FASB issued ASU 2017-09, Compensation-Stock Compensation (Topic 718) Scope of Modification Accounting. This amendment provides guidance concerning which changes to the terms or conditions of a share-based payment require an entity to apply modification accounting. Certain changes to stock awards, notably administrative changes, do not require modification accounting. There are three specific criteria that need to be met in order to prove that modification accounting is not required. ASU 2017-09 is effective for fiscal years, and interim period within those fiscal years, beginning after December 15, 2017, with early adoption permitted. The Company is evaluating the impact that ASU 2017-09 will have on its condensed consolidated financial statements and related disclosures.

Share-Based Compensation

Share-Based Compensation	9 Months Ended
	Sep. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation The Company has share-based incentive awards outstanding to its eligible employees and non-employee directors under three equity incentive plans: (i) the 2007 Stock Option Plan (the 2007 Plan), (ii) the 2009 Long-Term Incentive Plan (the 2009 Plan) and (iii) the 2016 Long-Term Incentive Plan. No further awards may be granted under the 2007 and 2009 Plans, although awards granted under the 2007 and 2009 Plans remain outstanding in accordance with their terms. Awards granted under the 2016 Plan may be in the form of stock options, restricted stock units and other forms of share-based incentives, including performance restricted stock units, stock appreciation rights and deferred stock rights. Stock Options For the three months ended September 30, 2017 and 2016 , the Company did no t recognize any share-based compensation expense related to stock option awards. For the nine months ended September 30, 2017 and 2016 , the Company did no t recognize any share-based compensation expense and recognized less than $0.1 million , respectively, related to stock option awards. No unrecognized compensation costs remained related to stock option awards as of September 30, 2017 . No stock options were granted during the three and nine months ended September 30, 2017 and September 30, 2016 . A summary of the stock option activity, weighted average exercise prices and options outstanding as of September 30, 2017 and 2016 is as follows: For the nine months ended September 30, 2017 2016 Common Stock Options Weighted Average Exercise Price Common Stock Options Weighted Average Exercise Price Outstanding at beginning of period: 2,167 $ 13.33 2,265 $ 13.16 Granted — $ — — $ — Exercised (37 ) $ 7.39 (87 ) $ 9.83 Expired or forfeited — $ — — $ — Outstanding at end of period: 2,130 $ 13.43 2,178 $ 13.29 Restricted Stock Unit Awards For the three months ended September 30, 2017 and September 30, 2016 , the Company recognized share-based compensation expense related to restricted stock unit awards of $1.1 million and $1.2 million , respectively. For the nine months ended September 30, 2017 and September 30, 2016 , the Company recognized share-based compensation expense related to restricted stock unit awards of $3.4 million for each respective period. As of September 30, 2017 , there was $8.1 million of unrecognized compensation costs, net of estimated forfeitures, related to restricted stock unit awards, which are expected to be recognized over a remaining weighted average period of 2.4 years . During the first nine months of 2017 and 2016 , the Company granted approximately 21,000 and 22,000 shares, respectively, of fully-vested common stock to its five non-employee directors, as provided for under the Company's non-employee director compensation plan. These shares had grant date fair values of $0.4 million and $0.5 million , respectively, which was recorded as share-based compensation expense during the nine months ended September 30, 2017 and September 30, 2016 , respectively. During the first nine months of 2017 and 2016 , approximately 175,000 and 182,000 restricted stock units vested for each period. The fair value of these units was $3.2 million and $4.5 million for each respective period. Upon vesting, restricted stock units are generally net share-settled to cover the required minimum withholding tax and the remaining amount is converted into an equivalent number of shares of common stock. A summary of the Company's outstanding, non-vested restricted share units is presented below: For the nine months ended September 30, 2017 2016 Units Weighted Units Weighted Outstanding at beginning of period: 569 $ 20.81 595 $ 18.89 Granted 124 $ 21.21 218 $ 24.51 Released (175 ) $ 20.61 (182 ) $ 19.66 Forfeited (30 ) $ 21.21 (26 ) $ 19.24 Outstanding at end of period: 488 $ 20.97 605 $ 20.68 Performance Restricted Stock Units The Company maintains Performance Restricted Stock Units (PRSUs) that have been granted to select executives and senior officers whose ultimate payout is based on the Company’s performance over a one -year period based on three metrics, as defined: (1) Operating Income, (2) Adjusted EBITDAS and (3) Revenue. There also is a discretionary portion of the PRSUs based on individual performance, at the discretion of the Compensation Committee (Discretionary PRSUs). PRSUs and Discretionary PRSUs generally vest ratably on each of the first four anniversary dates upon completion of the performance period, for a total requisite service period of up to five years and have no dividend rights. PRSUs are equity-classified and compensation costs are initially measured using the fair value of the underlying stock at the date of grant, assuming that the target performance conditions will be achieved. Compensation costs related to the PRSUs are subsequently adjusted for changes in the expected outcomes of the performance conditions. Discretionary PRSUs are liability-classified and adjusted to fair value (with a corresponding adjustment to compensation expense) based upon the targeted number of shares to be awarded and the fair value of the underlying stock each reporting period until approved by the Compensation Committee, at which point they are classified as equity. A summary of the Company's Performance Restricted Stock Unit activity is presented below: For the nine months ended September 30, 2017 Units Weighted Outstanding at beginning of period: 290 $ 16.01 Granted 128 $ 20.42 Performance condition adjustments (67 ) $ 20.55 Released (64 ) $ 14.87 Forfeited — $ — Outstanding at end of period: 287 $ 17.07 During the nine months ended September 30, 2017 , the Compensation Committee modified the awards issued during the transition period ended December 31, 2016 from a one -year performance period to a seven month performance period to align the awards with the change in the Company's fiscal year from May 31 to December 31. Accordingly, for the nine months ended September 30, 2017 , the Compensation Committee approved these transition period PRSUs, which resulted in a reduction of approximately 3,000 units. There was a reduction of approximately 64,000 units to the awards granted in 2017 during the nine months ended September 30, 2017 . As of September 30, 2017, the liability related to Discretionary PRSUs was less than $0.1 million and is classified within accrued expenses and other current liabilities on the condensed consolidated balance sheet. For the three months ended September 30, 2017 and September 30, 2016 , the Company recognized aggregate share-based compensation expense related to the awards described above of approximately $0.4 million and $0.5 million , respectively. For the nine months ended September 30, 2017 and September 30, 2016 , the Company recognized aggregate share-based compensation expense related to the awards described above of approximately $1.3 million for each respective period. At September 30, 2017 , there was $2.7 million of total unrecognized compensation costs related to approximately 287,000 non-vested performance restricted stock units, which are expected to be recognized over a remaining weighted average period of 2.1 years .

Earnings per Share

Earnings per Share	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Earnings per Share	Earnings per Share Basic earnings per share is computed by dividing net income by the weighted-average number of shares outstanding during the period. Diluted earnings per share is computed by dividing net income by the sum of (1) the weighted-average number of shares of common stock outstanding during the period, and (2) the dilutive effect of assumed conversion of equity awards using the treasury stock method. With respect to the number of weighted-average shares outstanding (denominator), diluted shares reflects: (i) the exercise of options to acquire common stock to the extent that the options’ exercise prices are less than the average market price of common shares during the period and (ii) the pro forma vesting of restricted stock units. The following table sets forth the computations of basic and diluted earnings per share: Three months ended Nine months ended September 30, 2017 September 30, 2016 September 30, 2017 September 30, 2016 Basic earnings (loss) per share: Numerator: Net income (loss) attributable to Mistras Group, Inc. $ (6,968 ) $ 7,238 $ (3,059 ) $ 13,446 Denominator: Weighted average common shares outstanding 28,274 29,051 28,465 28,966 Basic earnings (loss) per share $ (0.25 ) $ 0.25 $ (0.11 ) $ 0.46 Diluted earnings (loss) per share: Numerator: Net income (loss) attributable to Mistras Group, Inc. $ (6,968 ) $ 7,238 $ (3,059 ) $ 13,446 Denominator: Weighted average common shares outstanding 28,274 29,051 28,465 28,966 Dilutive effect of stock options outstanding n/a (1) 814 n/a (1) 810 Dilutive effect of restricted stock units outstanding n/a (2) 366 n/a (2) 363 28,274 30,231 28,465 30,139 Diluted earnings (loss) per share $ (0.25 ) $ 0.24 $ (0.11 ) $ 0.45 (1) - For the three and nine months ended September 30, 2017, 716 and 802 shares, respectively were excluded from the calculation of diluted EPS due to the net loss for the respective periods. (2) - For the three and nine months ended September 30, 2017, 308 and 337 shares, respectively, were excluded from the calculation of diluted EPS due to the net loss for the respective periods.

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2017
Business Combinations [Abstract]
Acquisitions	Acquisitions During the nine months ended September 30, 2017 , the Company completed two acquisitions, one that performs mechanical services at height, located in Canada, and a company located in the U.S. that primarily performs chemical and specialty process services, primarily in the aerospace industry. In these acquisitions, the Company acquired the assets of the U.S. acquiree and 100% of the common stock of the Canada acquiree in exchange for aggregate consideration of $8.5 million in cash, contingent consideration up to $5.9 million to be earned based upon the acquired business achieving specific performance metrics over the initial three years of operations from the acquisition date and $1.6 million for working capital adjustments yet to be finalized. The Company accounted for these transactions in accordance with the acquisition method of accounting for business combinations. The assets and liabilities of the businesses acquired in 2017 were included in the Company's condensed consolidated balance sheet based upon their estimated fair values on the date of acquisition as determined in a preliminary purchase price allocation, using available information and making assumptions management believes are reasonable. The Company is still in the process of completing its valuations of the assets acquired. The results of operations for these acquisitions are included in the Services segment's results from the date of acquisition. Goodwill of $4.3 million primarily relates to expected synergies and assembled workforce, of which $1.8 million is generally deductible for tax purposes. Other intangible assets, primarily related to customer relationships and covenants not to compete, were $8.4 million . The Company's preliminary purchase price allocations are included in the table below, summarizing the estimated fair value of the assets acquired and liabilities assumed at the date of acquisition: 2017 Number of Entities 2 Consideration transferred: Cash paid $ 8,509 Working capital adjustments 1,604 Contingent consideration 4,126 Consideration transferred $ 14,239 Current assets $ 2,443 Property, plant and equipment 1,140 Intangible assets 8,436 Goodwill 4,271 Current liabilities (881 ) Long-term deferred tax liability (1,170 ) Net assets acquired $ 14,239 Revenues and operating income included in the condensed consolidated statement of operations for 2017 from these acquisitions for the period subsequent to the closing of this transaction was approximately $9.1 million and $1.1 million , respectively. As these acquisitions were immaterial to the Company's 2017 results, no unaudited pro forma financial information has been included in this report for either acquisition. The Company completed two acquisitions that provide NDT services, located in Canada, during the nine months ended September 30, 2016 . The Company acquired 100% of the common stock of both acquirees in exchange for aggregate consideration of $1.2 million in cash, $0.3 million of notes payable and contingent consideration estimated to be $0.4 million to be earned based upon the acquired businesses achieving specific performance metrics over their initial three years of operations from their acquisition dates. Acquisition-Related Expense In the course of its acquisition activities, the Company incurs costs in connection with due diligence, professional fees, and other expenses. Additionally, the Company adjusts the fair value of acquisition-related contingent consideration liabilities on a quarterly basis. These amounts are recorded as acquisition-related expense (benefit), net, on the condensed consolidated statements of income and were as follows for the three and nine months ended September 30, 2017 and 2016 : Three months ended September 30, Nine months ended September 30, 2017 2016 2017 2016 Due diligence, professional fees and other transaction costs $ — $ 28 $ 291 $ 577 Adjustments to fair value of contingent consideration liabilities (248 ) 356 (880 ) (676 ) Acquisition-related expense (benefit), net $ (248 ) $ 384 $ (589 ) $ (99 )

Accounts Receivable, net

Accounts Receivable, net	9 Months Ended
	Sep. 30, 2017
Receivables [Abstract]
Accounts Receivable, net	Accounts Receivable, net Accounts receivable consisted of the following: September 30, 2017 December 31, 2016 Trade accounts receivable $ 144,503 $ 133,704 Allowance for doubtful accounts (4,314 ) (2,852 ) Accounts receivable, net $ 140,189 $ 130,852

Property, Plant and Equipment,

Property, Plant and Equipment, net	9 Months Ended
	Sep. 30, 2017
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, net	Property, Plant and Equipment, net Property, plant and equipment consisted of the following: Useful Life (Years) September 30, 2017 December 31, 2016 Land $ 1,909 $ 1,714 Buildings and improvements 30-40 22,735 19,261 Office furniture and equipment 5-8 13,941 12,574 Machinery and equipment 5-7 179,681 166,423 218,266 199,972 Accumulated depreciation and amortization (141,093 ) (126,823 ) Property, plant and equipment, net $ 77,173 $ 73,149 Depreciation expense for the three months ended September 30, 2017 and September 30, 2016 was $5.7 million and $5.8 million , respectively. Depreciation expense for the nine months ended September 30, 2017 and September 30, 2016 was $16.8 million and $17.6 million , respectively.

Goodwill

Goodwill	9 Months Ended
	Sep. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	Goodwill Changes in the carrying amount of goodwill by segment is shown below: Services International Products and Systems Total Balance at December 31, 2016 $ 123,392 $ 33,351 $ 13,197 $ 169,940 Goodwill acquired during the period 4,271 — — 4,271 Impairment charges — — (13,197 ) (13,197 ) Adjustments to preliminary purchase price allocations (211 ) — — (211 ) Foreign currency translation 1,028 3,873 — 4,901 Balance at September 30, 2017 $ 128,480 $ 37,224 $ — $ 165,704 The Company reviews goodwill for impairment on a reporting unit basis on October 1 of each year and whenever events or changes in circumstances indicate the carrying value of goodwill may not be recoverable. During the second quarter of 2017, there were pending contract bids which management assessed as having a reasonable chance of success. These contract bids were not awarded to the Company. As a result of this missed opportunity, the annual forecasting process was accelerated, resulting in lower future operating profits and cash flows. As such, there were indicators that the carrying amount of the goodwill for the Products and Systems reporting unit may not be recoverable due to the decline in the projected future cash flows. The Company performed an analysis to determine any impairment of long-lived assets (see Note 8) as well as an analysis to determine any impairment of goodwill. For the goodwill analysis, we used income and market approaches to estimate the fair value of the reporting unit, which requires significant judgment in evaluation of economic and industry trends, estimated future cash flows, discount rates and other factors, and compared that fair value to the carrying value, and determined that the fair value of the reporting unit was less than the carrying value. The Company recorded an impairment charge of $13.2 million , based on the difference between the fair value and the carrying value of the reporting unit, which resulted in an impairment of the entire amount of goodwill for the Products and Systems reporting unit. The Company's cumulative goodwill impairment as of September 30, 2017 was $23.1 million , of which $13.2 million related to the Products and Systems segment and $9.9 million related to the International segment. As of December 31, 2016, the cumulative goodwill impairment was $9.9 million , which is within its International segment.

Intangible Assets

Intangible Assets	9 Months Ended
	Sep. 30, 2017
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Intangible Assets	Intangible Assets The gross amount, accumulated amortization and net carrying amount of intangible assets were as follows: September 30, 2017 December 31, 2016 Useful Life (Years) Gross Amount Accumulated Amortization Impairment Net Carrying Amount Gross Amount Accumulated Amortization Net Carrying Amount Customer relationships 5-14 $ 92,488 $ (56,582 ) $ (170 ) $ 35,736 $ 81,559 $ (50,417 ) $ 31,142 Software/Technology 3-15 19,219 (13,804 ) (2,411 ) 3,004 18,128 (12,577 ) 5,551 Covenants not to compete 2-5 11,687 (10,227 ) — 1,460 11,143 (9,647 ) 1,496 Other 2-12 8,262 (6,188 ) (32 ) 2,042 7,266 (5,448 ) 1,818 Total $ 131,656 $ (86,801 ) $ (2,613 ) $ 42,242 $ 118,096 $ (78,089 ) $ 40,007 Amortization expense for the three months ended September 30, 2017 and September 30, 2016 was $2.4 million and $2.1 million , respectively. Amortization expense for the nine months ended September 30, 2017 and September 30, 2016 was $6.8 million and $6.9 million , respectively. As described in Note 7, the Company performed an analysis to determine whether there was any impairment of long-lived assets for the Products and Systems reporting unit. We used income and market approaches to estimate the fair value of the long-lived assets, which requires significant judgment in evaluation of the useful lives of the assets, economic and industry trends, estimated future cash flows, discount rates, and other factors. The result of the analysis was an impairment of $2.4 million to software/technology, $0.2 million to customer relationships and less than $0.1 million to other intangibles, which are included in the impairment charges line on the condensed consolidated statements of income for the three and nine months ended September 30, 2017.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	9 Months Ended
	Sep. 30, 2017
Payables and Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following: September 30, 2017 December 31, 2016 Accrued salaries, wages and related employee benefits $ 29,763 $ 23,442 Contingent consideration, current portion 2,999 1,826 Accrued workers’ compensation and health benefits 5,740 6,351 Deferred revenue 5,440 3,743 Litigation accrual 1,200 6,320 Other accrued expenses 20,466 17,015 Total accrued expenses and other liabilities $ 65,608 $ 58,697

Long-Term Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt Long-term debt consisted of the following: September 30, 2017 December 31, 2016 Senior credit facility $ 95,050 $ 82,776 Notes payable 230 320 Other 9,013 4,200 Total debt 104,293 87,296 Less: Current portion (2,490 ) (1,379 ) Long-term debt, net of current portion $ 101,803 $ 85,917 Senior Credit Facility The Company's revolving credit agreement with its banking group ("Credit Agreement") provides the Company with a $175.0 million revolving line of credit, which, under certain circumstances, can be increased to $225.0 million . The Company may borrow up to $30.0 million in non-U.S. Dollar currencies and use up to $10.0 million of the credit limit for the issuance of letters of credit. The Credit Agreement has a maturity date of October 30, 2019. As of September 30, 2017 , the Company had borrowings of $95.1 million and a total of $5.0 million of letters of credit outstanding under the Credit Agreement. Loans under the Credit Agreement bear interest at LIBOR plus an applicable LIBOR margin ranging from 1% to 1.75% , or a base rate less a margin of 1.25% to 0.375% , at the option of the Company, based upon the Company’s Funded Debt Leverage Ratio. Funded Debt Leverage Ratio is defined as the ratio of (1) all outstanding indebtedness for borrowed money and other interest-bearing indebtedness as of the date of determination to (2) EBITDA (which is (a) net income, less (b) income (or plus loss) from discontinued operations and extraordinary items, plus (c) income tax expenses, plus (d) interest expense, plus (e) depreciation, depletion, and amortization (including non-cash loss on retirement of assets), plus (f) stock compensation expense, less (g) cash expense related to stock compensation, plus or minus certain other adjustments) for the period of four consecutive fiscal quarters immediately preceding the date of determination. The Company has the benefit of the lowest margin if its Funded Debt Leverage Ratio is equal to or less than 0.5 to 1, and the margin increases as the ratio increases, to the maximum margin if the ratio is greater than 2.0 to 1. The Company will also bear additional costs for market disruption, regulatory changes effecting the lenders’ funding costs, and default pricing of an additional 2% interest rate margin on any amounts not paid when due. Amounts borrowed under the Credit Agreement are secured by liens on substantially all of the assets of the Company. The Credit Agreement contains financial covenants requiring that the Company maintain a Funded Debt Leverage Ratio of no greater than 3.25 to 1 and an Interest Coverage Ratio of at least 3.0 to 1. Interest Coverage Ratio is defined as the ratio, as of any date of determination, of (a) EBITDA for the 12 month period immediately preceding the date of determination, to (b) all interest, premium payments, debt discount, fees, charges and related expenses of the Company and its subsidiaries in connection with borrowed money (including capitalized interest) or in connection with the deferred purchase price of assets, in each case to the extent treated as interest in accordance with GAAP, paid during the 12 month period immediately preceding the date of determination. The Credit Agreement also limits the Company’s ability to, among other things, create liens, make investments, incur more indebtedness, merge or consolidate, make dispositions of property, pay dividends and make distributions to stockholders, enter into a new line of business, enter into transactions with affiliates and enter into burdensome agreements. The Credit Agreement does not limit the Company’s ability to acquire other businesses or companies except that the acquired business or company must be in the Company's line of business, the Company must be in compliance with the financial covenants on a pro forma basis after taking into account the acquisition, and, if the acquired business is a separate subsidiary, in certain circumstances the lenders will receive the benefit of a guaranty of the subsidiary and liens on its assets and a pledge of its stock. As of September 30, 2017 , the Company was in compliance with the terms of the Credit Agreement, and will continuously monitor its compliance with the covenants contained in its Credit Agreement. Notes Payable and Other In connection with certain of its acquisitions, the Company issued subordinated notes payable to the sellers. The maturity of the notes that remain outstanding are three years from the date of acquisition and bear interest at the prime rate for the Bank of Canada, currently 3.2% as of September 30, 2017. Interest expense is recorded in the condensed consolidated statements of income.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company performs fair value measurements in accordance with the guidance provided by ASC 820, Fair Value Measurements and Disclosures. ASC 820 defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Financial instruments measured at fair value on a recurring basis The fair value of contingent consideration liabilities was estimated using a discounted cash flow technique with significant inputs that are not observable in the market and thus represents a Level 3 fair value measurement as defined in ASC 820. The significant inputs in the Level 3 measurement not supported by market activity include the probability assessments of expected future cash flows related to the acquisitions, appropriately discounted considering the uncertainties associated with the obligation, and as calculated in accordance with the terms of the applicable acquisition agreements. The following table represents the changes in the fair value of Level 3 contingent consideration: Nine months ended September 30, 2017 Beginning balance $ 3,094 Acquisitions 4,126 Payments (554 ) Accretion of liability 198 Revaluation (1,078 ) Foreign currency translation 28 Ending balance $ 5,814 Financial instruments not measured at fair value on a recurring basis The Company has evaluated current market conditions and borrower credit quality and has determined that the carrying value of its long-term debt approximates fair value. The fair value of the Company’s notes payable and capital lease obligations approximates their carrying amounts based on anticipated interest rates which management believes would currently be available to the Company for similar issuances of debt.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Proceedings and Government Investigations The Company is subject to periodic lawsuits, investigations and claims that arise in the ordinary course of business. The Company cannot predict with certainty the ultimate resolution of lawsuits, investigations and claims asserted against it. Except possibly for certain of the matters described below, the Company does not believe that any currently pending legal proceeding to which the Company is a party will have a material adverse effect on its business, results of operations, cash flows or financial condition. The costs of defense and amounts that may be recovered against the Company may be covered by insurance for certain matters. The Company has accrued an aggregate of approximately $1.6 million for losses related to the matters described below, net of insurance, for which the Company has stated that an accrual has been established. This $1.6 million accrual does not include the California class action matter, described below, as to which the settlement amount has been fully paid. Litigation and Commercial Claims The Company settled a consolidated purported class and collective action that resulted from the consolidation of two cases originally filed in California state court in April 2015. In connection with the settlement, the Company recorded a pre-tax charge of $6.3 million during the three months ended June 30, 2016 and paid the settlement in February 2017. The Company is a defendant in the lawsuit AGL Services Company v. Mistras Group, Inc., pending in U.S. District Court for the Northern District of Georgia, filed November 2016. The case involves radiography work performed by the Company in 2013 on the construction of a pipeline project in the U.S. The owner of the pipeline project has claimed damages of approximately $5.8 million and contends that certain of the radiography images the Company’s technicians prepared regarding the project did not meet the code quality interpretation standards required by the American Petroleum Institute. At a trial concluded on October 26, 2017, the jury awarded the plaintiff damages plus interest, which the Company believes is fully covered by insurance. The Company’s subsidiary in France has been involved in a dispute with a former owner of a business purchased by the Company’s French subsidiary. The judgment is being appealed, but the Company recorded an accrual for the judgment during the three months ended June 30, 2016. The loss for this matter is included in the accrual set forth above. The Company is a defendant in a lawsuit, Triumph Aerostructures, LLC d/b/a Triumph Aerostructures-Vought Aircraft Division v. Mistras Group, Inc ., pending in Texas State district court, 193rd Judicial District, Dallas County, Texas, filed September 2016. The plaintiff alleges Mistras delivered a defective Ultrasonic inspection system in 2014 and is alleging damages of approximately $2.3 million . The Company has established an accrual for this matter, which is included in the amount set forth above. Government Investigations In May 2015, the Company received a notice from the U.S. Environmental Protection Agency (“EPA”) that it performed a preliminary assessment at a leased facility the Company operates in Cudahy, California. Based upon the preliminary assessment, the EPA is conducting an investigation of the site, which includes taking groundwater and soil samples. The purpose of the investigation is to determine whether any hazardous materials were released from the facility. The Company has been informed that certain hazardous materials and pollutants have been found in the ground water in the general vicinity of the site and the EPA is attempting to ascertain the origination or source of these materials and pollutants. Given the historic industrial use of the site, the EPA determined that the site of the Cudahy facility should be examined, along with numerous other sites in the vicinity. At this time, the Company is unable to determine whether it has any liability in connection with this matter and if so, the amount or range of any such liability, and accordingly, has not established any accruals for this matter. Acquisition-related contingencies The Company is liable for contingent consideration in connection with certain of its acquisitions. As of September 30, 2017 , total potential acquisition-related contingent consideration ranged from zero to approximately $8.6 million and would be payable upon the achievement of specific performance metrics by certain of the acquired companies over the next 2.8 years of operations. See Note 4 - Acquisitions to these condensed consolidated financial statements for further discussion of the Company’s acquisitions.

Segment Disclosure

Segment Disclosure	9 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Segment Disclosure	Segment Disclosure The Company’s three operating segments are: • Services. This segment provides asset protection solutions primarily in North America with the largest concentration in the United States and the Canadian services business, consisting primarily of non-destructive testing and inspection, mechanical and engineering services that are used to evaluate and maintain the structural integrity and reliability of critical energy, industrial and public infrastructure. • International. This segment offers services, products and systems similar to those of the Company’s other two segments to global markets, principally in Europe, the Middle East, Africa, Asia and South America, but not to customers in China and South Korea, which are served by the Products and Systems segment. • Products and Systems. This segment designs, manufactures, sells, installs and services the Company’s asset protection products and systems, including equipment and instrumentation, predominantly in the United States. Costs incurred for general corporate services, including finance, legal, and certain other costs that are provided to the segments are reported within Corporate and eliminations. Sales to the International segment from the Products and Systems segment and subsequent sales by the International segment of the same items are recorded and reflected in the operating performance of both segments. Additionally, engineering charges and royalty fees charged to the Services and International segments by the Products and Systems segment are reflected in the operating performance of each segment. All such intersegment transactions are eliminated in the Company’s consolidated financial reporting. Selected consolidated financial information by segment for the periods shown was as follows (intercompany transactions are eliminated in Corporate and eliminations): Three months ended Nine months ended September 30, 2017 September 30, 2016 September 30, 2017 September 30, 2016 Revenues Services $ 137,194 $ 127,153 $ 397,565 $ 395,089 International 38,200 37,922 106,360 105,275 Products and Systems 6,268 6,807 16,925 19,955 Corporate and eliminations (2,092 ) (3,071 ) (7,524 ) (5,713 ) $ 179,570 $ 168,811 $ 513,326 $ 514,606 Three months ended Nine months ended September 30, 2017 September 30, 2016 September 30, 2017 September 30, 2016 Gross profit Services $ 34,729 $ 33,704 $ 100,432 $ 102,652 International 10,432 13,133 29,720 33,673 Products and Systems 2,753 3,686 7,313 9,475 Corporate and eliminations (17 ) 128 (73 ) 356 $ 47,897 $ 50,651 $ 137,392 $ 146,156 Three months ended Nine months ended September 30, 2017 September 30, 2016 September 30, 2017 September 30, 2016 Income (loss) from operations Services $ 11,699 $ 12,221 $ 31,211 $ 30,932 International 1,023 5,751 3,866 8,925 Products and Systems (15,573 ) 806 (16,913 ) 560 Corporate and eliminations (7,524 ) (6,662 ) (20,287 ) (17,816 ) $ (10,375 ) $ 12,116 $ (2,123 ) $ 22,601 Income (loss) by operating segment includes intercompany transactions, which are eliminated in Corporate and eliminations. Three months ended Nine months ended September 30, 2017 September 30, 2016 September 30, 2017 September 30, 2016 Depreciation and amortization Services $ 5,543 $ 5,516 $ 16,330 $ 17,224 International 2,004 1,958 5,736 5,881 Products and Systems 594 552 1,746 1,718 Corporate and eliminations (46 ) (107 ) (168 ) (260 ) $ 8,095 $ 7,919 $ 23,644 $ 24,563 September 30, 2017 December 31, 2016 Intangible assets, net Services $ 24,951 $ 19,550 International 14,228 14,139 Products and Systems 2,309 5,482 Corporate and eliminations 754 836 $ 42,242 $ 40,007 September 30, 2017 December 31, 2016 Total assets Services $ 306,323 $ 291,539 International 150,555 130,427 Products and Systems 13,944 28,964 Corporate and eliminations 13,600 18,497 $ 484,422 $ 469,427 Revenues by geographic area for the three and nine months ended September 30, 2017 and 2016 , respectively, were as follows: Three months ended Nine months ended September 30, 2017 September 30, 2016 September 30, 2017 September 30, 2016 Revenues United States $ 114,249 $ 113,409 $ 344,808 $ 358,343 Other Americas 26,084 16,940 59,452 48,828 Europe 36,264 33,126 97,630 93,265 Asia-Pacific 2,973 5,336 11,436 14,170 $ 179,570 $ 168,811 $ 513,326 $ 514,606

Repurchase of Common Stock

Repurchase of Common Stock	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Repurchase of Common Stock	Repurchase of Common Stock On October 7, 2015, the Company's Board of Directors approved a $50 million stock repurchase plan. As part of this plan, on August 17, 2016, the Company entered into an agreement with its CEO, Dr. Sotirios Vahaviolos, to purchase up to 1 million of his shares, commencing in October 2016. Pursuant to the agreement, in general, the Company will purchase from Dr. Vahaviolos up to $2 million of shares each month, at a 2% discount to the average daily closing price of the Company's common stock for the preceding month. During the nine months ended September 30, 2017, the Company purchased approximately 726,000 shares from Dr. Vahaviolos at an average price of $21.93 per share and an aggregate cost of $15.9 million . From the inception of the plan through September 30, 2017, the Company has purchased 1,000,000 shares from Dr. Vahaviolos at an average price of $21.92 per share for an aggregate cost of approximately $21.9 million and approximately 146,000 shares in the open market at an average price of $20.48 per share for an aggregate cost of approximately $3.0 million . All such repurchased shares are classified as Treasury Stock on the condensed consolidated balance sheet. As of September 30, 2017, approximately $25.1 million remained available to repurchase shares under the stock repurchase plan.

Description of Business and B21

Description of Business and Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The condensed consolidated financial statements contained in this report are unaudited. In the opinion of management, the condensed consolidated financial statements include all adjustments, which are of a normal recurring nature, necessary for a fair presentation of the results for the interim periods of the fiscal years ending December 31, 2017 and 2016 . Certain items included in these statements are based on management’s estimates. Actual results may differ from those estimates. The results of operations for any interim period are not necessarily indicative of the results expected for the year. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the notes to the audited consolidated financial statements contained in the Company’s Transition Report on Form 10-K (“2016 Transition Report”) for the transition period ended December 31, 2016 , as filed with the Securities and Exchange Commission on March 20, 2017 .
Principles of Consolidation	Principles of Consolidation The accompanying unaudited condensed consolidated financial statements include the accounts of Mistras Group, Inc. and its wholly and majority-owned subsidiaries. For subsidiaries in which the Company’s ownership interest is less than 100%, the non-controlling interests are reported in stockholders’ equity in the accompanying condensed consolidated balance sheets. The non-controlling interests in net income, net of tax, is classified separately in the accompanying condensed consolidated statements of income. All significant intercompany accounts and transactions have been eliminated in consolidation. On January 3, 2017, the Company's Board of Directors approved a change in the Company's fiscal year end from May 31 to December 31, effective December 31, 2016. The transition period was for the seven months ended December 31, 2016 ("the transition period"). Prior to this change, the Company's International segment was consolidated on a one month lag. Therefore, for this interim report, the condensed consolidated income statements include a one month lag for the International segment for the three and nine months ended September 30, 2016. Management does not believe that any events occurred during the one-month lag period that would have a material effect on the Company’s condensed consolidated financial statements. The one - month lag was removed with the change in the Company's fiscal year noted above, and accordingly, the condensed consolidated income statements do not include a one month lag for the International segment's results for the three and nine months ended September 30, 2017.
Reclassification	Reclassification Certain amounts in prior periods have been reclassified to conform to the current year presentation. Such reclassifications did not have a material effect on the Company's financial condition or results of operations as previously reported.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In August 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date, which defers the effective date of ASU 2014-09 for all entities by one year. This update is effective for public business entities for annual reporting periods beginning after December 15, 2017, including interim periods within those reporting periods. Earlier application is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. ASU 2014-09 will become effective for us beginning 2018, which is when we plan to adopt this standard. The ASU permits two methods of adoption: retrospectively to each prior reporting period presented (full retrospective method), or retrospectively with the cumulative effect of initially applying the guidance recognized at the date of initial application (the cumulative catch-up transition method). The ASU also requires expanded disclosures relating to the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. Additionally, qualitative and quantitative disclosures are required about customer contracts, significant judgments and changes in judgments, and assets recognized from the costs to obtain or fulfill a contract. The Company plans to adopt this guidance using the cumulative catch-up method. We are still in the process of evaluating the effect of adoption on our condensed consolidated financial statements and are currently assessing our contracts with customers across each of its global operating segments. Our assessment is not yet complete and therefore we are unable to quantify the potential impacts. However, as most of our projects are short-term in nature and billed on at time and materials basis, we do not currently anticipate that the adoption of ASU 2014-09 will result in substantial changes to the overall pattern or timing of our revenue recognition. In November 2015, the FASB issued ASU No. 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes. This amendment will simplify the presentation of deferred tax assets and liabilities on the balance sheet and require all deferred tax assets and liabilities to be treated as non-current. ASU 2015-17 is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2016, with early adoption permitted. The Company adopted this guidance prospectively beginning in the first quarter of 2017, which did not have a material impact on the condensed consolidated financial statements and related disclosures. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842). This amendment supersedes previous accounting guidance ( Topic 840) and requires all leases, with the exception of leases with a term of 12 months or less, to be recorded on the balance sheet as lease assets and lease liabilities. ASU 2016-02 is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2018, with early adoption permitted. The standard requires lessees and lessors to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. The Company is evaluating the effect that ASU 2016-02 will have on its condensed consolidated financial statements and related disclosures. In March 2016, the FASB issued ASU No. 2016-09, Stock Compensation (Topic 718). This amendment simplifies certain aspects of accounting for share-based payment transactions, which include accounting for income taxes and the related impact on the statement of cash flows, an option to account for forfeitures when they occur in addition to the existing guidance to estimate the forfeitures of awards, classification of awards as either equity or liabilities and classification on the statement of cash flows for employee taxes paid to tax authorities on shares withheld for vesting. ASU 2016-09 is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2016, with early adoption permitted. The Company adopted this guidance prospectively beginning in the first quarter of 2017, and accordingly, is recording excess tax benefits and tax deficiencies as a component of income tax expense. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230). This amendment will provide guidance on the presentation and classification of specific cash flow items to improve consistency within the statement of cash flows. ASU 2016-15 is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2017, with early adoption permitted. The Company is evaluating the impact that ASU 2016-15 will have on its condensed consolidated financial statements and related disclosures. In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230). This amendment will clarify the presentation of restricted cash on the statement of cash flows. Amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning and ending cash balances on the statement of cash flows. ASU 2016-18 is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2017, with early adoption permitted. The Company does not expect that ASU 2016-18 will have a material impact on its condensed consolidated financial statements and related disclosures. In January 2017, the FASB issued ASU No. 2017-04, Intangibles-Goodwill and Other (Topic 350). This amendment eliminates Step Two of the goodwill impairment test. Under the amendments in this update, entities should perform the annual goodwill impairment test by comparing the carrying value of its reporting units to their fair value. An entity should record an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value. Tax deductibility of goodwill should be considered in evaluating any reporting unit's impairment loss to be taken. ASU 2017-04 is effective for fiscal years beginning after December 15, 2019, with early adoption permitted. The Company has early adopted ASU 2017-04 in the third quarter of 2017 for its condensed consolidated financial statements and related disclosures. See Notes 7 and 8 for information on the impairment of assets in the Products and Systems reporting unit during the three months ended September 30, 2017. In May 2017, the FASB issued ASU 2017-09, Compensation-Stock Compensation (Topic 718) Scope of Modification Accounting. This amendment provides guidance concerning which changes to the terms or conditions of a share-based payment require an entity to apply modification accounting. Certain changes to stock awards, notably administrative changes, do not require modification accounting. There are three specific criteria that need to be met in order to prove that modification accounting is not required. ASU 2017-09 is effective for fiscal years, and interim period within those fiscal years, beginning after December 15, 2017, with early adoption permitted. The Company is evaluating the impact that ASU 2017-09 will have on its condensed consolidated financial statements and related disclosures.
Fair Value Measurements	Financial instruments not measured at fair value on a recurring basis The Company has evaluated current market conditions and borrower credit quality and has determined that the carrying value of its long-term debt approximates fair value. The fair value of the Company’s notes payable and capital lease obligations approximates their carrying amounts based on anticipated interest rates which management believes would currently be available to the Company for similar issuances of debt. Fair Value Measurements The Company performs fair value measurements in accordance with the guidance provided by ASC 820, Fair Value Measurements and Disclosures. ASC 820 defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Financial instruments measured at fair value on a recurring basis The fair value of contingent consideration liabilities was estimated using a discounted cash flow technique with significant inputs that are not observable in the market and thus represents a Level 3 fair value measurement as defined in ASC 820. The significant inputs in the Level 3 measurement not supported by market activity include the probability assessments of expected future cash flows related to the acquisitions, appropriately discounted considering the uncertainties associated with the obligation, and as calculated in accordance with the terms of the applicable acquisition agreements.

Share-Based Compensation (Table

Share-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of stock option activity, weighted average exercise prices and options outstanding	A summary of the stock option activity, weighted average exercise prices and options outstanding as of September 30, 2017 and 2016 is as follows: For the nine months ended September 30, 2017 2016 Common Stock Options Weighted Average Exercise Price Common Stock Options Weighted Average Exercise Price Outstanding at beginning of period: 2,167 $ 13.33 2,265 $ 13.16 Granted — $ — — $ — Exercised (37 ) $ 7.39 (87 ) $ 9.83 Expired or forfeited — $ — — $ — Outstanding at end of period: 2,130 $ 13.43 2,178 $ 13.29
Summary of Company's outstanding, nonvested restricted share units and performance restricted stock units activity	A summary of the Company's Performance Restricted Stock Unit activity is presented below: For the nine months ended September 30, 2017 Units Weighted Outstanding at beginning of period: 290 $ 16.01 Granted 128 $ 20.42 Performance condition adjustments (67 ) $ 20.55 Released (64 ) $ 14.87 Forfeited — $ — Outstanding at end of period: 287 $ 17.07 A summary of the Company's outstanding, non-vested restricted share units is presented below: For the nine months ended September 30, 2017 2016 Units Weighted Units Weighted Outstanding at beginning of period: 569 $ 20.81 595 $ 18.89 Granted 124 $ 21.21 218 $ 24.51 Released (175 ) $ 20.61 (182 ) $ 19.66 Forfeited (30 ) $ 21.21 (26 ) $ 19.24 Outstanding at end of period: 488 $ 20.97 605 $ 20.68

Earnings per Share (Tables)

Earnings per Share (Tables)	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Schedule of computations of basic and diluted earnings per share	The following table sets forth the computations of basic and diluted earnings per share: Three months ended Nine months ended September 30, 2017 September 30, 2016 September 30, 2017 September 30, 2016 Basic earnings (loss) per share: Numerator: Net income (loss) attributable to Mistras Group, Inc. $ (6,968 ) $ 7,238 $ (3,059 ) $ 13,446 Denominator: Weighted average common shares outstanding 28,274 29,051 28,465 28,966 Basic earnings (loss) per share $ (0.25 ) $ 0.25 $ (0.11 ) $ 0.46 Diluted earnings (loss) per share: Numerator: Net income (loss) attributable to Mistras Group, Inc. $ (6,968 ) $ 7,238 $ (3,059 ) $ 13,446 Denominator: Weighted average common shares outstanding 28,274 29,051 28,465 28,966 Dilutive effect of stock options outstanding n/a (1) 814 n/a (1) 810 Dilutive effect of restricted stock units outstanding n/a (2) 366 n/a (2) 363 28,274 30,231 28,465 30,139 Diluted earnings (loss) per share $ (0.25 ) $ 0.24 $ (0.11 ) $ 0.45 (1) - For the three and nine months ended September 30, 2017, 716 and 802 shares, respectively were excluded from the calculation of diluted EPS due to the net loss for the respective periods. (2) - For the three and nine months ended September 30, 2017, 308 and 337 shares, respectively, were excluded from the calculation of diluted EPS due to the net loss for the respective periods.

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2017
Business Combinations [Abstract]
Schedule of Preliminary Purchase Price Allocation	The Company's preliminary purchase price allocations are included in the table below, summarizing the estimated fair value of the assets acquired and liabilities assumed at the date of acquisition: 2017 Number of Entities 2 Consideration transferred: Cash paid $ 8,509 Working capital adjustments 1,604 Contingent consideration 4,126 Consideration transferred $ 14,239 Current assets $ 2,443 Property, plant and equipment 1,140 Intangible assets 8,436 Goodwill 4,271 Current liabilities (881 ) Long-term deferred tax liability (1,170 ) Net assets acquired $ 14,239
Schedule of Acquisition-Related Expenses	In the course of its acquisition activities, the Company incurs costs in connection with due diligence, professional fees, and other expenses. Additionally, the Company adjusts the fair value of acquisition-related contingent consideration liabilities on a quarterly basis. These amounts are recorded as acquisition-related expense (benefit), net, on the condensed consolidated statements of income and were as follows for the three and nine months ended September 30, 2017 and 2016 : Three months ended September 30, Nine months ended September 30, 2017 2016 2017 2016 Due diligence, professional fees and other transaction costs $ — $ 28 $ 291 $ 577 Adjustments to fair value of contingent consideration liabilities (248 ) 356 (880 ) (676 ) Acquisition-related expense (benefit), net $ (248 ) $ 384 $ (589 ) $ (99 )

Accounts Receivable, net (Table

Accounts Receivable, net (Tables)	9 Months Ended
	Sep. 30, 2017
Receivables [Abstract]
Schedule of accounts receivable	Accounts receivable consisted of the following: September 30, 2017 December 31, 2016 Trade accounts receivable $ 144,503 $ 133,704 Allowance for doubtful accounts (4,314 ) (2,852 ) Accounts receivable, net $ 140,189 $ 130,852

Property, Plant and Equipment26

Property, Plant and Equipment, net (Tables)	9 Months Ended
	Sep. 30, 2017
Property, Plant and Equipment [Abstract]
Schedule of Property, plant and equipment	Property, plant and equipment consisted of the following: Useful Life (Years) September 30, 2017 December 31, 2016 Land $ 1,909 $ 1,714 Buildings and improvements 30-40 22,735 19,261 Office furniture and equipment 5-8 13,941 12,574 Machinery and equipment 5-7 179,681 166,423 218,266 199,972 Accumulated depreciation and amortization (141,093 ) (126,823 ) Property, plant and equipment, net $ 77,173 $ 73,149

Goodwill (Tables)

Goodwill (Tables)	9 Months Ended
	Sep. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	Changes in the carrying amount of goodwill by segment is shown below: Services International Products and Systems Total Balance at December 31, 2016 $ 123,392 $ 33,351 $ 13,197 $ 169,940 Goodwill acquired during the period 4,271 — — 4,271 Impairment charges — — (13,197 ) (13,197 ) Adjustments to preliminary purchase price allocations (211 ) — — (211 ) Foreign currency translation 1,028 3,873 — 4,901 Balance at September 30, 2017 $ 128,480 $ 37,224 $ — $ 165,704

Intangible Assets (Tables)

Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2017
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Schedule of gross amount, accumulated amortization and net carrying amount of intangible assets	The gross amount, accumulated amortization and net carrying amount of intangible assets were as follows: September 30, 2017 December 31, 2016 Useful Life (Years) Gross Amount Accumulated Amortization Impairment Net Carrying Amount Gross Amount Accumulated Amortization Net Carrying Amount Customer relationships 5-14 $ 92,488 $ (56,582 ) $ (170 ) $ 35,736 $ 81,559 $ (50,417 ) $ 31,142 Software/Technology 3-15 19,219 (13,804 ) (2,411 ) 3,004 18,128 (12,577 ) 5,551 Covenants not to compete 2-5 11,687 (10,227 ) — 1,460 11,143 (9,647 ) 1,496 Other 2-12 8,262 (6,188 ) (32 ) 2,042 7,266 (5,448 ) 1,818 Total $ 131,656 $ (86,801 ) $ (2,613 ) $ 42,242 $ 118,096 $ (78,089 ) $ 40,007

Accrued Expenses and Other Cu29

Accrued Expenses and Other Current Liabilities (Tables)	9 Months Ended
	Sep. 30, 2017
Payables and Accruals [Abstract]
Schedule of accrued expenses and other current liabilities	Accrued expenses and other current liabilities consisted of the following: September 30, 2017 December 31, 2016 Accrued salaries, wages and related employee benefits $ 29,763 $ 23,442 Contingent consideration, current portion 2,999 1,826 Accrued workers’ compensation and health benefits 5,740 6,351 Deferred revenue 5,440 3,743 Litigation accrual 1,200 6,320 Other accrued expenses 20,466 17,015 Total accrued expenses and other liabilities $ 65,608 $ 58,697

Long-Term Debt (Tables)

Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
Schedule of long-term debt	Long-term debt consisted of the following: September 30, 2017 December 31, 2016 Senior credit facility $ 95,050 $ 82,776 Notes payable 230 320 Other 9,013 4,200 Total debt 104,293 87,296 Less: Current portion (2,490 ) (1,379 ) Long-term debt, net of current portion $ 101,803 $ 85,917

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Schedule of changes in fair value of Level 3 contingent consideration	The following table represents the changes in the fair value of Level 3 contingent consideration: Nine months ended September 30, 2017 Beginning balance $ 3,094 Acquisitions 4,126 Payments (554 ) Accretion of liability 198 Revaluation (1,078 ) Foreign currency translation 28 Ending balance $ 5,814

Segment Disclosure (Tables)

Segment Disclosure (Tables)	9 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Schedule of consolidated financial information by segment	Selected consolidated financial information by segment for the periods shown was as follows (intercompany transactions are eliminated in Corporate and eliminations): Three months ended Nine months ended September 30, 2017 September 30, 2016 September 30, 2017 September 30, 2016 Revenues Services $ 137,194 $ 127,153 $ 397,565 $ 395,089 International 38,200 37,922 106,360 105,275 Products and Systems 6,268 6,807 16,925 19,955 Corporate and eliminations (2,092 ) (3,071 ) (7,524 ) (5,713 ) $ 179,570 $ 168,811 $ 513,326 $ 514,606 Three months ended Nine months ended September 30, 2017 September 30, 2016 September 30, 2017 September 30, 2016 Gross profit Services $ 34,729 $ 33,704 $ 100,432 $ 102,652 International 10,432 13,133 29,720 33,673 Products and Systems 2,753 3,686 7,313 9,475 Corporate and eliminations (17 ) 128 (73 ) 356 $ 47,897 $ 50,651 $ 137,392 $ 146,156 Three months ended Nine months ended September 30, 2017 September 30, 2016 September 30, 2017 September 30, 2016 Income (loss) from operations Services $ 11,699 $ 12,221 $ 31,211 $ 30,932 International 1,023 5,751 3,866 8,925 Products and Systems (15,573 ) 806 (16,913 ) 560 Corporate and eliminations (7,524 ) (6,662 ) (20,287 ) (17,816 ) $ (10,375 ) $ 12,116 $ (2,123 ) $ 22,601 Income (loss) by operating segment includes intercompany transactions, which are eliminated in Corporate and eliminations. Three months ended Nine months ended September 30, 2017 September 30, 2016 September 30, 2017 September 30, 2016 Depreciation and amortization Services $ 5,543 $ 5,516 $ 16,330 $ 17,224 International 2,004 1,958 5,736 5,881 Products and Systems 594 552 1,746 1,718 Corporate and eliminations (46 ) (107 ) (168 ) (260 ) $ 8,095 $ 7,919 $ 23,644 $ 24,563 September 30, 2017 December 31, 2016 Intangible assets, net Services $ 24,951 $ 19,550 International 14,228 14,139 Products and Systems 2,309 5,482 Corporate and eliminations 754 836 $ 42,242 $ 40,007 September 30, 2017 December 31, 2016 Total assets Services $ 306,323 $ 291,539 International 150,555 130,427 Products and Systems 13,944 28,964 Corporate and eliminations 13,600 18,497 $ 484,422 $ 469,427
Schedule of revenues by geographic area	Revenues by geographic area for the three and nine months ended September 30, 2017 and 2016 , respectively, were as follows: Three months ended Nine months ended September 30, 2017 September 30, 2016 September 30, 2017 September 30, 2016 Revenues United States $ 114,249 $ 113,409 $ 344,808 $ 358,343 Other Americas 26,084 16,940 59,452 48,828 Europe 36,264 33,126 97,630 93,265 Asia-Pacific 2,973 5,336 11,436 14,170 $ 179,570 $ 168,811 $ 513,326 $ 514,606

Description of Business and B33

Description of Business and Basis of Presentation (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017customer	Sep. 30, 2016customer	Sep. 30, 2017mocustomer	Sep. 30, 2016customer	May 31, 2016
Concentration Risk [Line Items]
Period lag in the consolidation of International segment subsidiaries (months)			1 month		1 month
Number of months less than the actual number of months from the acquisition date for which results of international segment subsidiaries are included in consolidation (months) | mo			1
Customer Concentration Risk | Services | Revenues
Concentration Risk [Line Items]
Concentration risk, number of customers	1	1	1	1
Concentration risk, percentage	10.00%	14.00%	11.00%	12.00%
Customer Concentration Risk | Services | Accounts Receivable
Concentration Risk [Line Items]
Concentration risk, number of customers			1
Concentration risk, percentage			8.00%

Share-Based Compensation - Equi

Share-Based Compensation - Equity Incentive Plans (Details)	9 Months Ended
	Sep. 30, 2017planshares
Share-based compensation
Number of employee stock ownership plans (plan) | plan	3
2007 Plan
Share-based compensation
Number of awards that may be granted (in shares)	0
2009 Plan
Share-based compensation
Number of awards that may be granted (in shares)	0

Share-Based Compensation - Stoc

Share-Based Compensation - Stock Options (Details) - Stock Options - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Common Stock Options (in shares)
Outstanding at the beginning of the period: (in shares)			2,167,000	2,265,000
Granted (in shares)	0	0	0	0
Exercised (in shares)			(37,000)	(87,000)
Expired of forfeited (in shares)			0	0
Outstanding at the end of the period: (in shares)	2,130,000	2,178,000	2,130,000	2,178,000
Weighted Average Exercise Price (in dollar per share)
Outstanding at the beginning of period: (in dollars per share)			$ 13.33	$ 13.16
Granted (in dollars per share)			0	0
Exercised (in dollars per share)			7.39	9.83
Expired or forfeited (in dollars per share)			0	0
Outstanding at the end of period: (in dollars per share)	$ 13.43	$ 13.29	$ 13.43	$ 13.29
Recognized share-based compensation expense (less than)	$ 0	$ 0	$ 0	$ 100,000
Unrecognized compensation costs	$ 0		$ 0

Share-Based Compensation - Rest

Share-Based Compensation - Restricted Stock Unit Awards - Narrative (Details) - Restricted Stock Units shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)directorshares	Sep. 30, 2016USD ($)directorshares
Share-based compensation
Recognized share-based compensation expense (benefit)	$ 1,100	$ 1,200	$ 3,400	$ 3,400
Unrecognized compensation cost, net of estimated forfeitures	$ 8,100		$ 8,100
Weighted-average period over which unrecognized compensation cost is expected to be recognized (years)			2 years 4 months 24 days
Fair value of shares vested			$ 3,200	$ 4,500
Shares vested (in shares) | shares			175	182
Non-employee directors
Share-based compensation
Fair value of shares vested			$ 21	$ 22
Number of non-employee directors to whom fully vested common stock is granted (director) | director			5	5
Number of fully vested common stock granted (in shares) | shares			400	500

Share-Based Compensation - Re37

Share-Based Compensation - Restricted Stock Units Awards - Activity (Details) - Restricted Stock Units - $ / shares shares in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Restricted Stock Units Awards (Units)
Outstanding at beginning of period: (in shares)	569	595
Granted (in shares)	124	218
Released (in shares)	(175)	(182)
Forfeited (in shares)	(30)	(26)
Outstanding at end of period: (in shares)	488	605
Weighted Average Grant-Date Fair Value (in dollars per share)
Outstanding at the beginning of period: (in dollars per share)	$ 20.81	$ 18.89
Granted (in dollars per share)	21.21	24.51
Released (in dollars per share)	20.61	19.66
Forfeited (in dollars per share)	21.21	19.24
Outstanding at end of period: (in dollars per share)	$ 20.97	$ 20.68

Share-Based Compensation - Perf

Share-Based Compensation - Performance Restricted Stock Units - Narrative (Details) - Performance Restricted Stock Units shares in Thousands, $ in Millions	3 Months Ended		7 Months Ended	9 Months Ended
	Sep. 30, 2017USD ($)shares	Sep. 30, 2016USD ($)	Dec. 31, 2016shares	Sep. 30, 2017USD ($)performance_metricshares	Sep. 30, 2016USD ($)
Share-based compensation
Performance period (years)			1 year	7 months
Nonvested shares outstanding (in shares) | shares	287		290	287
Fiscal 2016 Grants
Share-based compensation
Performance period (years)				1 year
Number of performance award metrics | performance_metric				3
Requisite service period (years)				5 years
Recognized share-based compensation expense (benefit) | $	$ 0.4	$ 0.5		$ 1.3	$ 1.3
Unrecognized compensation cost | $	$ 2.7			$ 2.7
Nonvested shares outstanding (in shares) | shares	287			287
Weighted-average period over which unrecognized compensation cost is expected to be recognized (years)				2 years 1 month 24 days
Fiscal 2016 Grants | Anniversary 1
Share-based compensation
Award vesting rights, percentage				25.00%
Fiscal 2016 Grants | Anniversary 2
Share-based compensation
Award vesting rights, percentage				25.00%
Fiscal 2016 Grants | Anniversary 3
Share-based compensation
Award vesting rights, percentage				25.00%
Fiscal 2016 Grants | Anniversary 4
Share-based compensation
Award vesting rights, percentage				25.00%
Fiscal 2016 Grants | Executive and Senior Officers
Share-based compensation
Reduction in nonvested shares authorized (in shares) | shares	64			3
Fiscal 2016 Grants | Executive and Senior Officers | Accrued expenses and other liabilities
Share-based compensation
Accrued liability related to discretionary PRSUs | $	$ 0.1			$ 0.1

Share-Based Compensation - Pe39

Share-Based Compensation - Performance Restricted Stock Units - Activity (Details) - Performance Restricted Stock Units shares in Thousands	9 Months Ended
	Sep. 30, 2017$ / sharesshares
Performance Restricted Stock (Units)
Outstanding at beginning of period: (in shares) | shares	290
Granted (in shares) | shares	128
Performance condition adjustments (in shares) | shares	(67)
Released (in shares) | shares	(64)
Forfeited (in shares) | shares	0
Outstanding at end of period: (in shares) | shares	287
Weighted Average Grant-Date Fair Value (in dollars per share)
Outstanding at the beginning of period: (in dollars per share) | $ / shares	$ 16.01
Granted (in dollars per share) | $ / shares	20.42
Performance condition adjustments (in dollars per share) | $ / shares	20.55
Released (in dollars per share) | $ / shares	14.87
Forfeited (in dollars per share) | $ / shares	0
Outstanding at end of period: (in dollars per share) | $ / shares	$ 17.07

Earnings per Share (Details)

Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Basic earnings (loss) per share:
Net income (loss) attributable to Mistras Group, Inc.	$ (6,968)	$ 7,238	$ (3,059)	$ 13,446
Denominator:
Weighted average common shares outstanding (in shares)	28,274,000	29,051,000	28,465,000	28,966,000
Basic earnings (loss) per share (in dollars per share)	$ (0.25)	$ 0.25	$ (0.11)	$ 0.46
Denominator:
Weighted average common shares outstanding (in shares)	28,274,000	29,051,000	28,465,000	28,966,000
Dilutive effect of stock options outstanding (in shares)		814,000		810,000
Dilutive effect of restricted stock units outstanding (in shares)		366,000		363,000
Weighted average common shares outstanding, diluted (in shares)	28,274,000	30,231,000	28,465,000	30,139,000
Diluted earnings (loss) per share (in dollars per share)	$ (0.25)	$ 0.24	$ (0.11)	$ 0.45
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	716,000		802,000
Restricted Stock Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	308,000		337,000

Acquisitions - Narrative (Detai

Acquisitions - Narrative (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)entity	Sep. 30, 2016USD ($)entity	Dec. 31, 2016USD ($)
Acquisitions
Goodwill	$ 165,704		$ 169,940
Fiscal 2017 Acquisitions
Acquisitions
Number of acquisitions | entity	2
Cash paid for acquisitions	$ 8,509
Contingent consideration from acquisitions	4,126
Acquisition working capital adjustments	1,604
Goodwill	4,271
Other intangible assets acquired	8,436
Revenues from acquisitions	9,100
Operating income from acquisitions	$ 1,100
Fiscal 2017 Acquisitions | U.S.
Acquisitions
Number of acquisitions | entity	2
Cash paid for acquisitions	$ 8,500
Contingent consideration from acquisitions	$ 5,900
Initial period over which potential acquisition-related contingent consideration would be payable	3 years
Acquisition working capital adjustments	$ 1,600
Goodwill	4,300
Goodwill deductible for tax purposes	1,800
Fiscal 2017 Acquisitions | U.S. | Customer Relationships and Covenants Not To Compete
Acquisitions
Other intangible assets acquired	$ 8,400
Fiscal 2017 Acquisitions | Canada
Acquisitions
Number of acquisitions | entity	1
Percentage of interest acquired	100.00%
Fiscal 2016 Acquisitions | Canada
Acquisitions
Number of acquisitions | entity		2
Cash paid for acquisitions		$ 1,200
Contingent consideration from acquisitions		$ 400
Initial period over which potential acquisition-related contingent consideration would be payable		3 years
Percentage of interest acquired		100.00%
Notes payable assumed in acquisitions		$ 300

Acquisitions - Preliminary Purc

Acquisitions - Preliminary Purchase Price Allocation (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)entity	Dec. 31, 2016USD ($)
Consideration transferred:
Goodwill	$ 165,704	$ 169,940
Fiscal 2017 Acquisitions
Acquisitions
Number of Entities | entity	2
Consideration transferred:
Cash paid	$ 8,509
Working capital adjustments	1,604
Contingent consideration	4,126
Consideration transferred	14,239
Current assets	2,443
Property, plant and equipment	1,140
Intangible assets	8,436
Goodwill	4,271
Current liabilities	(881)
Long-term deferred tax liability	(1,170)
Net assets acquired	$ 14,239

Acquisitions - Acquisition-Rela

Acquisitions - Acquisition-Related Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Acquisitions
Acquisition-related expense (benefit), net	$ (248)	$ 384	$ (589)	$ (99)
Fiscal 2017 Acquisitions
Acquisitions
Due diligence, professional fees and other transaction costs	0		291
Adjustments to fair value of contingent consideration liabilities	(248)		(880)
Acquisition-related expense (benefit), net	$ (248)		$ (589)
Fiscal 2016 Acquisitions
Acquisitions
Due diligence, professional fees and other transaction costs		28		577
Adjustments to fair value of contingent consideration liabilities		356		(676)
Acquisition-related expense (benefit), net		$ 384		$ (99)

Accounts Receivable, net (Detai

Accounts Receivable, net (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Receivables [Abstract]
Trade accounts receivable	$ 144,503	$ 133,704
Allowance for doubtful accounts	(4,314)	(2,852)
Accounts receivable, net	$ 140,189	$ 130,852

Property, Plant and Equipment45

Property, Plant and Equipment, net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Property, Plant and Equipment, net
Property, plant and equipment, gross	$ 218,266		$ 218,266		$ 199,972
Accumulated depreciation and amortization	(141,093)		(141,093)		(126,823)
Property, plant and equipment, net	77,173		77,173		73,149
Depreciation expense	5,700	$ 5,800	16,800	$ 17,600
Land
Property, Plant and Equipment, net
Property, plant and equipment, gross	1,909		1,909		1,714
Buildings and improvements
Property, Plant and Equipment, net
Property, plant and equipment, gross	22,735		$ 22,735		19,261
Buildings and improvements | Minimum
Property, Plant and Equipment, net
Useful Life (Years)			30 years
Buildings and improvements | Maximum
Property, Plant and Equipment, net
Useful Life (Years)			40 years
Office furniture and equipment
Property, Plant and Equipment, net
Property, plant and equipment, gross	13,941		$ 13,941		12,574
Office furniture and equipment | Minimum
Property, Plant and Equipment, net
Useful Life (Years)			5 years
Office furniture and equipment | Maximum
Property, Plant and Equipment, net
Useful Life (Years)			8 years
Machinery and equipment
Property, Plant and Equipment, net
Property, plant and equipment, gross	$ 179,681		$ 179,681		$ 166,423
Machinery and equipment | Minimum
Property, Plant and Equipment, net
Useful Life (Years)			5 years
Machinery and equipment | Maximum
Property, Plant and Equipment, net
Useful Life (Years)			7 years

Goodwill (Details)

Goodwill (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)
Goodwill [Roll Forward]
Balance at December 31, 2016	$ 169,940
Goodwill acquired during the period	4,271
Impairment charges	(13,197)
Adjustments to preliminary purchase price allocations	(211)
Foreign currency translation	4,901
Balance at September 30, 2017	165,704
Services
Goodwill [Roll Forward]
Balance at December 31, 2016	123,392
Goodwill acquired during the period	4,271
Impairment charges	0
Adjustments to preliminary purchase price allocations	(211)
Foreign currency translation	1,028
Balance at September 30, 2017	128,480
International
Goodwill [Roll Forward]
Balance at December 31, 2016	33,351
Goodwill acquired during the period	0
Impairment charges	0
Adjustments to preliminary purchase price allocations	0
Foreign currency translation	3,873
Balance at September 30, 2017	37,224
Products and Systems
Goodwill [Roll Forward]
Balance at December 31, 2016	13,197
Goodwill acquired during the period	0
Impairment charges	(13,197)
Adjustments to preliminary purchase price allocations	0
Foreign currency translation	0
Balance at September 30, 2017	$ 0

Goodwill - Narrative (Details)

Goodwill - Narrative (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Goodwill [Line Items]
Goodwill impairment charges	$ 13,197
Goodwill cumulative impairment loss	23,100
Products and Systems
Goodwill [Line Items]
Goodwill impairment charges	13,197
Goodwill cumulative impairment loss	13,200
International
Goodwill [Line Items]
Goodwill impairment charges	0
Goodwill cumulative impairment loss	$ 9,900	$ 9,900

Intangible Assets (Details)

Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 131,656	$ 118,096
Accumulated Amortization	(86,801)	(78,089)
Impairment	(2,613)
Net Carrying Amount	42,242	40,007
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Amount	92,488	81,559
Accumulated Amortization	(56,582)	(50,417)
Impairment	(170)
Net Carrying Amount	$ 35,736	31,142
Customer relationships | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	5 years
Customer relationships | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	14 years
Software/Technology
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 19,219	18,128
Accumulated Amortization	(13,804)	(12,577)
Impairment	(2,411)
Net Carrying Amount	$ 3,004	5,551
Software/Technology | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	3 years
Software/Technology | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	15 years
Covenants not to compete
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 11,687	11,143
Accumulated Amortization	(10,227)	(9,647)
Impairment	0
Net Carrying Amount	$ 1,460	1,496
Covenants not to compete | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	2 years
Covenants not to compete | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	5 years
Other
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 8,262	7,266
Accumulated Amortization	(6,188)	(5,448)
Impairment	(32)
Net Carrying Amount	$ 2,042	$ 1,818
Other | Minimum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	2 years
Other | Maximum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	12 years

Intangible Assets - Narrative (

Intangible Assets - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 2.4	$ 2.1	$ 6.8	$ 6.9
Software/Technology
Finite-Lived Intangible Assets [Line Items]
Impairment of intangible assets	2.4
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Impairment of intangible assets	0.2
Other
Finite-Lived Intangible Assets [Line Items]
Impairment of intangible assets	$ 0.1

Accrued Expenses and Other Cu50

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Accrued salaries, wages and related employee benefits	$ 29,763	$ 23,442
Contingent consideration, current portion	2,999	1,826
Accrued workers’ compensation and health benefits	5,740	6,351
Deferred revenue	5,440	3,743
Litigation accrual	1,200	6,320
Other accrued expenses	20,466	17,015
Total accrued expenses and other liabilities	$ 65,608	$ 58,697

Long-Term Debt - Schedule of Lo

Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term debt	$ 104,293	$ 87,296
Less: Current portion	(2,490)	(1,379)
Long-term debt, net of current portion	101,803	85,917
Senior credit facility
Debt Instrument [Line Items]
Long-term debt	95,050	82,776
Notes payable
Debt Instrument [Line Items]
Long-term debt	230	320
Other
Debt Instrument [Line Items]
Long-term debt	$ 9,013	$ 4,200

Long-Term Debt - Narrative (Det

Long-Term Debt - Narrative (Details)	Oct. 31, 2014quarter	Sep. 30, 2017USD ($)
Senior credit facility
Senior Credit Facility
Maximum borrowing capacity		$ 175,000,000
Line of credit facility, higher borrowing capacity option		225,000,000
Maximum borrowing capacity in non-U.S. Dollar currencies		30,000,000
Maximum amount available for the issuance of letters of credit		10,000,000
Outstanding borrowings		95,100,000
Outstanding letters of credit		$ 5,000,000
Number of consecutive fiscal quarters used for calculating funded debt leverage ratio | quarter	4
Funded debt leverage ratio at which the entity will have the benefit of lowest interest margin (less than or equal to)	0.5
Funded debt leverage ratio at which the entity will bear the maximum interest rate margin (greater than)	2
Additional interest rate margin if funded debt leverage ratio exceeds threshold (as a percent)	2.00%
Funded debt leverage ratio for additional interest payment (less than)	3.25
Interest coverage ratio (greater than)	3
Preceding period used for calculating Interest Coverage Ratio	12 months
Senior credit facility | LIBOR
Senior Credit Facility
Reference rate, description	LIBOR
Senior credit facility | LIBOR | Minimum
Senior Credit Facility
Margin (as a percent)	1.00%
Senior credit facility | LIBOR | Maximum
Senior Credit Facility
Margin (as a percent)	1.75%
Senior credit facility | Base rate
Senior Credit Facility
Reference rate, description	base rate
Senior credit facility | Base rate | Minimum
Senior Credit Facility
Margin (as a percent)	(0.375%)
Senior credit facility | Base rate | Maximum
Senior Credit Facility
Margin (as a percent)	(1.25%)
Notes payable
Notes Payable and Other
Interest rate (as a percent)		3.20%
Notes payable | Minimum
Notes Payable and Other
Maturity term from the date of acquisition		3 years

Fair Value Measurements (Detail

Fair Value Measurements (Details) - Level 3 $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)
Contingent Consideration Liability [Roll Forward]
Beginning balance	$ 3,094
Acquisitions	4,126
Payments	(554)
Accretion of liability	198
Revaluation	(1,078)
Foreign currency translation	28
Ending balance	$ 5,814

Commitments and Contingencies (

Commitments and Contingencies (Details)	1 Months Ended			3 Months Ended			9 Months Ended
	Nov. 30, 2016USD ($)	Sep. 30, 2016USD ($)	Apr. 30, 2015claim	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)
Litigation
Loss contingency accrual				$ 1,600,000			$ 1,600,000
Settlement charge				1,200,000	$ 0		1,200,000	$ 6,320,000
Consolidated class and collective action lawsuit | Settled Litigation
Litigation
Number of consolidated claims settled | claim			2
Settlement charge						$ 6,300,000
Lawsuits for alleged quality defects | Pending Litigation
Litigation
Amount of damages claimed	$ 5,800,000
Defective ultrasound inspection system | Pending Litigation
Litigation
Amount of damages claimed		$ 2,300,000
Acquisition-related contingencies
Litigation
Potential acquisition-related contingent consideration, low end of range				0			0
Potential acquisition-related contingent consideration, high end of range				$ 8,600,000			$ 8,600,000
Remaining period over which potential acquisition-related contingent consideration would be payable							2 years 9 months 18 days

Segment Disclosure - Financial

Segment Disclosure - Financial Information by Segment (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)segment	Sep. 30, 2016USD ($)	Dec. 31, 2016USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment			3
Financial information by segment
Revenues	$ 179,570	$ 168,811	$ 513,326	$ 514,606
Gross profit	47,897	50,651	137,392	146,156
Income (loss) from operations	(10,375)	12,116	(2,123)	22,601
Depreciation and amortization	8,095	7,919	23,644	24,563
Intangible assets, net	42,242		42,242		$ 40,007
Total assets	484,422		484,422		469,427
Operating segments | Services
Financial information by segment
Revenues	137,194	127,153	397,565	395,089
Gross profit	34,729	33,704	100,432	102,652
Income (loss) from operations	11,699	12,221	31,211	30,932
Depreciation and amortization	5,543	5,516	16,330	17,224
Intangible assets, net	24,951		24,951		19,550
Total assets	306,323		306,323		291,539
Operating segments | International
Financial information by segment
Revenues	38,200	37,922	106,360	105,275
Gross profit	10,432	13,133	29,720	33,673
Income (loss) from operations	1,023	5,751	3,866	8,925
Depreciation and amortization	2,004	1,958	5,736	5,881
Intangible assets, net	14,228		14,228		14,139
Total assets	150,555		150,555		130,427
Operating segments | Products and Systems
Financial information by segment
Revenues	6,268	6,807	16,925	19,955
Gross profit	2,753	3,686	7,313	9,475
Income (loss) from operations	(15,573)	806	(16,913)	560
Depreciation and amortization	594	552	1,746	1,718
Intangible assets, net	2,309		2,309		5,482
Total assets	13,944		13,944		28,964
Corporate and eliminations
Financial information by segment
Revenues	(2,092)	(3,071)	(7,524)	(5,713)
Gross profit	(17)	128	(73)	356
Income (loss) from operations	(7,524)	(6,662)	(20,287)	(17,816)
Depreciation and amortization	(46)	$ (107)	(168)	$ (260)
Intangible assets, net	754		754		836
Total assets	$ 13,600		$ 13,600		$ 18,497

Segment Disclosure - Revenues b

Segment Disclosure - Revenues by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenue and long-lived assets by geographic area
Revenues	$ 179,570	$ 168,811	$ 513,326	$ 514,606
United States
Revenue and long-lived assets by geographic area
Revenues	114,249	113,409	344,808	358,343
Other Americas
Revenue and long-lived assets by geographic area
Revenues	26,084	16,940	59,452	48,828
Europe
Revenue and long-lived assets by geographic area
Revenues	36,264	33,126	97,630	93,265
Asia-Pacific
Revenue and long-lived assets by geographic area
Revenues	$ 2,973	$ 5,336	$ 11,436	$ 14,170

Repurchase of Common Stock (Det

Repurchase of Common Stock (Details) - Stock Repurchase Plan - USD ($)	Aug. 17, 2016	Sep. 30, 2017	Sep. 30, 2017	Oct. 07, 2015
Class of Stock [Line Items]
Stock repurchase plan, amount approved				$ 50,000,000
Treasury stock repurchased (in shares)			146,000
Treasury stock acquired, average price (in dollars per share)			$ 20.48
Treasury stock acquired, aggregate cost			$ 3,000,000
Stock repurchase plan, remaining amount approved		$ 25,100,000	$ 25,100,000
Chairman and CEO
Class of Stock [Line Items]
Stock repurchase plan, amount approved (in shares)	1,000,000
Stock repurchase plan, amount approved each month from CEO	$ 2,000,000
Average daily price of common stock for the preceding month discount, percent	2.00%
Treasury stock repurchased (in shares)		726,000	1,000,000
Treasury stock acquired, average price (in dollars per share)		$ 21.93	$ 21.92
Treasury stock acquired, aggregate cost		$ 15,900,000	$ 21,900,000