Mistras (MG) 10-Q8 Jan 162016 Q2 Quarterly reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Nov. 30, 2015	Jan. 01, 2016
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	Nov. 30, 2015
Amendment Flag	false
Current Fiscal Year End Date	--05-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		28,890,796
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q2

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Nov. 30, 2015	May. 31, 2015
Current Assets
Cash and cash equivalents	$ 10,579	$ 10,555
Accounts receivable, net	149,173	133,228
Inventories	9,676	10,841
Deferred income taxes	4,816	5,144
Prepaid expenses and other current assets	12,181	11,698
Total current assets	186,425	171,466
Property, plant and equipment, net	76,429	79,256
Intangible assets, net	46,759	51,276
Goodwill	167,649	166,414
Deferred income taxes	827	1,208
Other assets	1,975	2,107
Total assets	480,064	471,727
Current Liabilities
Accounts payable	9,169	10,529
Accrued expenses and other current liabilities	58,933	55,914
Current portion of long-term debt	13,772	17,902
Current portion of capital lease obligations	6,853	8,646
Income taxes payable	2,083	532
Total current liabilities	90,810	93,523
Long-term debt, net of current portion	87,946	95,557
Obligations under capital leases, net of current portion	10,240	10,717
Deferred income taxes	18,247	16,984
Other long-term liabilities	8,477	9,934
Total liabilities	$ 215,720	$ 226,715
Commitments and contingencies
Equity
Preferred stock, 10,000,000 shares authorized	$ 0	$ 0
Common stock, $0.01 par value, 200,000,000 shares authorized	289	287
Additional paid-in capital	210,222	208,064
Retained earnings	75,872	57,581
Accumulated other comprehensive loss	(22,149)	(21,113)
Total Mistras Group, Inc. stockholders’ equity	264,234	244,819
Noncontrolling interests	110	193
Total equity	264,344	245,012
Total liabilities and equity	$ 480,064	$ 471,727

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Nov. 30, 2015	May. 31, 2015
Statement of Financial Position [Abstract]
Preferred stock, shares authorized	10,000,000	10,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000

Unaudited Condensed Consolidate

Unaudited Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2015	Nov. 30, 2014
Income Statement [Abstract]
Revenue	$ 194,786	$ 206,893	$ 374,639	$ 373,466
Cost of revenue	132,720	142,940	256,120	262,662
Depreciation	5,141	4,914	10,320	9,771
Gross profit	56,925	59,039	108,199	101,033
Selling, general and administrative expenses	34,008	37,180	69,844	72,400
Research and engineering	601	629	1,222	1,278
Depreciation and amortization	2,822	3,472	5,603	6,894
Acquisition-related (benefit), net	(75)	(434)	(971)	(1,395)
Income from operations	19,569	18,192	32,501	21,856
Interest expense	1,335	1,352	3,257	2,257
Income before provision for income taxes	18,234	16,840	29,244	19,599
Provision for income taxes	6,804	6,428	10,967	7,516
Net income	11,430	10,412	18,277	12,083
Less: net loss (income) attributable to noncontrolling interests, net of taxes	(5)	15	20	10
Net income attributable to Mistras Group, Inc.	$ 11,425	$ 10,427	$ 18,297	$ 12,093
Earnings per common share
Basic (in dollars per share)	$ 0.40	$ 0.36	$ 0.64	$ 0.42
Diluted (in dollars per share)	$ 0.39	$ 0.35	$ 0.62	$ 0.41
Weighted average common shares outstanding:
Basic (in shares)	28,869	28,619	28,796	28,547
Diluted (in shares)	29,594	29,397	29,641	29,551

Unaudited Condensed Consolidat5

Unaudited Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2015	Nov. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 11,430	$ 10,412	$ 18,277	$ 12,083
Other comprehensive (loss):
Foreign currency translation adjustments	(384)	(6,011)	(1,036)	(7,916)
Comprehensive income	11,046	4,401	17,241	4,167
Less: comprehensive loss (income) attributable to noncontrolling interest	(5)	15	20	10
Comprehensive income attributable to Mistras Group, Inc.	$ 11,041	$ 4,416	$ 17,261	$ 4,177

Unaudited Condensed Consolidat6

Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Nov. 30, 2015	Nov. 30, 2014
Cash flows from operating activities
Net income	$ 18,277	$ 12,083
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	15,923	16,665
Deferred income taxes	1,809	1,192
Share-based compensation expense	3,227	4,257
Fair value adjustment to contingent consideration liabilities	(1,068)	(1,546)
Other	(259)	968
Changes in operating assets and liabilities, net of effect of acquisitions of businesses:
Accounts receivable	(17,641)	(24,196)
Inventories	1,496	601
Prepaid expenses and other current assets	(790)	(2,952)
Other assets	(9)	(478)
Accounts payable	(1,248)	(972)
Accrued expenses and other current liabilities	5,226	(2,074)
Income taxes payable	1,581	(395)
Net cash provided by operating activities	26,524	3,153
Cash flows from investing activities
Purchase of property, plant and equipment	(7,753)	(7,862)
Purchase of intangible assets	(480)	(433)
Acquisition of businesses, net of cash acquired	(1,709)	(32,661)
Proceeds from sale of equipment	319	596
Net cash used in investing activities	(9,623)	(40,360)
Cash flows from financing activities
Repayment of capital lease obligations	(3,681)	(4,183)
Proceeds from borrowings of long-term debt	1,968	872
Repayment of long-term debt	(15,870)	(10,726)
Proceeds of revolver	39,200	86,500
Repayments of revolver	(36,800)	(23,200)
Payment of contingent consideration for business acquisitions	(394)	(700)
Taxes paid related to net share settlement of share-based awards	(951)	(1,384)
Excess tax benefit from share-based compensation	(303)	283
Proceeds from the exercise of stock options	187	0
Net cash (used in) provided by financing activities	(16,644)	47,462
Effect of exchange rate changes on cash and cash equivalents	(233)	(676)
Net change in cash and cash equivalents	24	9,579
Cash and cash equivalents
Beginning of period	10,555	10,020
End of period	10,579	19,599
Supplemental disclosure of cash paid
Interest	3,010	1,815
Income taxes	6,223	8,028
Noncash investing and financing
Equipment acquired through capital lease obligations	1,555	3,533
Issuance of notes payable	$ 0	$ 20,500

Description of Business and Bas

Description of Business and Basis of Presentation	6 Months Ended
Description of Business and Basis of Presentation	Nov. 30, 2015
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) and non-destructive testing (NDT) 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 May 31, 2016 and 2015 . Reference to a fiscal year means the fiscal year ended May 31 . 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 consolidated financial statements contained in the Company’s Annual Report on Form 10-K (“Annual Report”) for fiscal 2015 , as filed with the Securities and Exchange Commission on August 12, 2015 . 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 noncontrolling interests are reported in stockholders’ equity in the accompanying consolidated balance sheets. The noncontrolling interests in net income, net of tax, is classified separately in the accompanying consolidated statements of income. All significant intercompany accounts and transactions have been eliminated in consolidation. Mistras Group, Inc.’s and its subsidiaries’ fiscal years end on May 31 except for the subsidiaries in the International segment, which end on April 30. Accordingly, the Company’s International segment subsidiaries are consolidated on a one month lag. Therefore, in the quarter and year of acquisition, results of acquired subsidiaries in the International segment are generally included in consolidated results for one less month than the actual number of months from the acquisition date to the end of the reporting period. Management does not believe that any events occurred during the one-month lag period that would have a material effect on the Company’s consolidated financial statements. 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. Immaterial Correction Subsequent to the issuance of its interim consolidated financial statements as of and for the three and six months ended November 30, 2014, the Company identified errors related to the classification of amounts reported in the Consolidated Statement of Cash Flows for that period. In accordance with the SEC Staff Accounting Bulletin (SAB) No. 99, Materiality, and SAB No. 108, Considering the Effects of Prior Year Misstatements when Quantifying Misstatements in Current Year Financial Statements, management evaluated the materiality of the errors from qualitative and quantitative perspectives, and concluded that the errors were immaterial. Accordingly, management has corrected the presentation of the affected line items of the accompanying consolidated statement of cash flows for the six-months ended November 30, 2014, as summarized below. These changes did not impact the Company’s net income, balance sheet, or stockholders’ equity for any period previously reported. Previously Reported Revised Cash flows from operating activities Fair value adjustment to contingent consideration liabilities (808 ) (1,546 ) Accounts payable (666 ) (972 ) Accrued expenses and other current liabilities (3,041 ) (2,074 ) Net cash provided by operating activities 3,230 3,153 Cash flows from investing activities Acquisition of businesses, net of cash acquired (32,967 ) (32,661 ) Net cash used in investing activities (40,666 ) (40,360 ) Cash flows from financing activities Proceeds from long-term debt — 872 Repayment of long-term debt (9,854 ) (10,726 ) Net borrowings against revolver 62,648 63,300 Net cash provided by financing activities 46,810 47,462 Effect of exchange rate changes on cash and cash equivalents 205 (676 ) Significant Accounting Policies The Company’s significant accounting policies are disclosed in Note 2 — Summary of Significant Accounting Policies in the Company's Annual 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 2015 Annual Report, there have been no material changes to the Company's significant accounting policies. Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU No. 2014-09, Revenue from Contracts with Customers , which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The ASU will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The new standard is effective for fiscal years and interim periods within those fiscal years beginning December 15, 2017, as a result of a one year deferral in the standard issued by the FASB in August 2015 with ASU 2015-14, Revenue from Contracts with Customers - Deferral of the Effective Date. Early application is not permitted. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures. In February 2015, the FASB issued ASU No. 2015-02, Consolidation (Topic 810): Amendments to the Consolidations Analysis , which changes the guidance for evaluating whether to consolidate certain legal entities. Specifically, the amendments modify the evaluation of whether limited partnerships and similar legal entities are variable interest entities ("VIEs") or voting interest entities. Further, the amendments eliminate the presumption that a general partner should consolidate a limited partnership, as well as affect the consolidation analysis of reporting entities that are involved with VIEs, particularly those that have fee arrangements and related party relationships. The updated guidance is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2015. Early adoption is permitted. The Company does not expect this update to have a material impact on the consolidated financial statements and related disclosures. In September 2015, the FASB issued ASU No. 2015-16, Business Combinations (Topic 805): Simplifying the Accounting for Measurement-Period Adjustments. This amendment will simplify the accounting for adjustments made to provisional amounts recognized in a business combination and eliminates the requirement to retrospectively account for those adjustments in previous reporting periods. This update will require on the face of the income statement or in the notes to the financial statements the amount recorded in current-period earnings that would have previously been recorded if the adjustment to the provisional amounts had been recognized as of the acquisition date. ASU 2015-16 is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2015. This update should be applied prospectively and earlier adoption is permitted for financial statements that have not been issued. The Company is evaluating the effect that ASU 2015-16 will have on its consolidated financial statements and related disclosures. 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 is evaluating the effect that ASU 2015-17 will have on its consolidated financial statements and related disclosures.

Share-Based Compensation

Share-Based Compensation	6 Months Ended
Share-Based Compensation	Nov. 30, 2015
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 Directors under two equity incentive plans: (i) the 2007 Stock Option Plan (the 2007 Plan), and (ii) the 2009 Long-Term Incentive Plan (the 2009 Plan). No further awards may be granted under the 2007 Plan, although awards granted under the 2007 Plan remain outstanding in accordance with their terms. Awards granted under the 2009 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 November 30, 2015 and 2014 , the Company recognized share-based compensation expense related to stock option awards of less than $0.1 million for each period respectively. For the six months ended November 30, 2015 and 2014 , the Company recognized share-based compensation expense related to stock option awards of less than $0.1 million for each period respectively. As of November 30, 2015 , there was less than $0.1 million of unrecognized compensation costs, net of estimated forfeitures, related to stock option awards, which are expected to be recognized over a remaining weighted average period of 0.3 years . No stock options were granted during the six months ended November 30, 2015 and 2014 . Restricted Stock Unit Awards For the three months ended November 30, 2015 and 2014 , the Company recognized share-based compensation expense related to restricted stock unit awards of $1.1 million and $ 1.2 million , respectively. For the six months ended November 30, 2015 and 2014 , the Company recognized share-based compensation expense related to restricted stock unit awards of $ 2.2 million and $ 2.3 million , respectively. As of November 30, 2015 , there was $9.5 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 2.6 years . During the first six months of fiscal 2016 and 2015 , the Company granted approximately 15,000 and 10,000 shares, respectively, of fully-vested common stock to its five non-employee directors, in connection with its non-employee director compensation plan. These shares had grant date fair values of $0.2 million for each period respectively, which was recorded as share-based compensation expense during the six months ended November 30, 2015 and 2014 . During the first six months of fiscal 2016 and 2015 , approximately 217,000 and 226,000 restricted stock units, respectively, vested. The fair value of these units was $3.4 million and $4.9 million , respectively. 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. Performance Restricted Stock Units Fiscal 2016 In the first quarter of fiscal 2016, the Company modified its equity compensation plan and granted 154,000 performance restricted stock units to its executive and certain other senior officers. These units have requisite service periods of five years and have no dividend rights. The actual payout of these units will vary based on the Company’s performance over a one -year period based on three metrics related to the Company’s fiscal 2016 performance: (1) Operating Income, (2) Adjusted EBITDAS, which is consistent with Adjusted EBITDA as disclosed in the financial statements, which is net income before interest, taxes, depreciation, amortization, non-cash stock-based compensation expense, acquisition related items, and other non-routine items as determined by the Committee and (3) Revenue. There is also a discretionary portion based on individual performance. During the second quarter of fiscal 2016, the Company evaluated the expected performance metrics and adjusted the estimated performance shares by 80,000 units to 234,000 units. As a condition for receiving any awards under the revised fiscal 2016 plan, the executive and senior officers surrendered and released all rights to receive any shares under the 2014 and 2015 awards with a three -year performance or market condition. The Company has accounted for the fiscal 2016 awards as modifications in accordance with ASC 718, Compensation - Stock Compensation. Compensation costs are initially measured assuming that the target performance conditions will be achieved. However, compensation costs related to the performance conditions are adjusted for subsequent changes in the expected outcomes of the performance conditions. The discretionary portion of these awards are liability-classified and adjusted to fair value each reporting period. Compensation costs for the discretionary portion of the awards are recognized over the same five year requisite service period as the awards based on the Company’s fiscal 2016 performance. For the three months ended November 30, 2015 , the Company recognized share-based compensation expense related to these units of approximately $0.2 million . For the six months ended November 30, 2015 , the Company recognized share-based compensation expense related to these units of approximately $0.2 million . At November 30, 2015 , there was $3.8 million of total unrecognized compensation costs related to the 234,000 non-vested performance restricted stock units, which are expected to be recognized over a remaining weighted average period of 4.1 years . Fiscal 2015 In the second quarter of fiscal 2015, the Company granted performance restricted stock units to its executive and certain other senior officers. These units were surrendered as part of the revised fiscal 2016 plan as discussed above. For the three and six months ended November 30, 2015, there was $0 and $0.2 million of compensation expense recognized, respectively. For the three and six months ended November 30, 2014, the Company recognized share-based compensation expense related to performance restricted stock units of $0.1 million and $0.1 million , respectively. Fiscal 2014 In the third quarter of fiscal 2014, the Company granted one -year, two -year and three -year performance restricted stock units to its executive officers and certain other senior officers. The three-year performance restricted stock units were surrendered as part of the revised fiscal 2016 plan as discussed above. For the three and six months ended November 30, 2015, there was $0 and $0.4 million of compensation expense recognized, respectively. For the three and six months ended November 30, 2014, the Company recognized share-based compensation expense related to performance restricted stock units of $0.8 million and $1.6 million , respectively.

Earnings per Share

Earnings per Share	6 Months Ended
Earnings per Share	Nov. 30, 2015
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) only 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 November 30, Six months ended November 30, 2015 2014 2015 2014 Basic earnings per share Numerator: Net income attributable to Mistras Group, Inc. $ 11,425 $ 10,427 $ 18,297 $ 12,093 Denominator: Weighted average common shares outstanding 28,869 28,619 28,796 28,547 Basic earnings per share $ 0.40 $ 0.36 $ 0.64 $ 0.42 Diluted earnings per share: Numerator: Net income attributable to Mistras Group, Inc. $ 11,425 $ 10,427 $ 18,297 $ 12,093 Denominator: Weighted average common shares outstanding 28,869 28,619 28,796 28,547 Dilutive effect of stock options outstanding 592 675 610 763 Dilutive effect of restricted stock units outstanding 133 103 235 241 29,594 29,397 29,641 29,551 Diluted earnings per share $ 0.39 $ 0.35 $ 0.62 $ 0.41

Acquisitions

Acquisitions	6 Months Ended
Acquisitions	Nov. 30, 2015
Business Combinations [Abstract]
Acquisitions	Acquisitions Acquisitions In the first half of fiscal 2016, the Company completed one acquisition. The Company purchased a company that provides unmanned aerial systems and NDT services, located in the U.S. In this acquisition, the Company acquired 100% of the common stock of the acquiree in exchange for consideration of $1.8 million in cash and contingent consideration estimated to be $0.9 million to be earned based upon the acquired business achieving specific performance metrics over the initial four years of operations from the acquisition date. The Company accounted for this transaction in accordance with the acquisition method of accounting for business combinations. The assets and liabilities of the business acquired in fiscal 2016 were included in the Company's 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 valuation of the assets, both tangible and intangible, and liabilities acquired. The results of operations for this acquisition is included in the Services segment's results from the date of acquisition. 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: Fiscal 2016 Number of Entities 1 Consideration transferred: Cash paid $ 1,750 Contingent consideration 945 Consideration transferred 2,695 Current assets 145 Property, plant and equipment 485 Goodwill 2,658 Current liabilities (521 ) Long-term deferred tax liability (72 ) Net assets acquired $ 2,695 In the first half of fiscal 2015, the Company completed three acquisitions. The Company purchased a company, located in Louisiana, a provider of maintenance and inspection services primarily on offshore platforms. This acquisition expanded the service offerings within the Services segment, allowing the Company to provide services to the upstream operations of its customers. The Company also purchased a group of asset protection businesses located in Quebec, Canada to complement service offerings within the Company’s Services segment and continue its market expansion strategy. The Company’s International Segment completed an acquisition of an asset inspection business located in the United Kingdom. In these acquisitions, the Company acquired 100% of the common stock or certain assets of each acquiree in exchange for aggregate consideration of approximately $34.0 million in cash and $22.7 million in notes payable issued as part of the acquisitions and other liabilities assumed. The Company accounted for these transactions in accordance with the acquisition method of accounting for business combinations. In addition, the acquisition in Quebec provided for contingent consideration of up to $2.7 million to be earned based upon the acquired business achieving specific performance metrics over the initial three years of operation from the acquisition date. The amortization period of intangible assets acquired in fiscal 2015 ranges from 3 to 10 years. The Company recorded $43.9 million of goodwill in connection with these acquisitions, reflecting the strategic fit and revenue and earnings growth potential of these business. Acquisition-Related Expense During the three and six month periods ended November 30, 2015 , the Company incurred acquisition-related costs of less than $0.1 million in connection with due diligence, professional fees, and other expenses for its acquisition activities. Additionally, the Company adjusted the fair value of certain previously recorded acquisition-related contingent consideration liabilities. These adjustments resulted in a net decrease of acquisition-related contingent consideration liabilities and a corresponding increase in income from operations of $0.2 million and $1.1 million , for the three and six month periods ended November 30, 2015 , respectively. The Company’s aggregate acquisition-related contingent consideration liabilities were $5.7 million and $6.4 million as of November 30, 2015 and May 31, 2015 , respectively. During the three and six month periods ended November 30, 2014 , the Company incurred acquisition-related costs of less than $0.2 million in connection with due diligence, professional fees, and other expenses for its acquisition activities. Additionally, the Company adjusted the fair value of certain acquisition-related contingent consideration liabilities. For the three and six month periods ended November 30, 2014 , these adjustments resulted in a net decrease of acquisition-related contingent consideration liabilities and a corresponding increase in income from operations of $0.6 million and $1.6 million , respectively. The fair value adjustments to acquisition-related contingent consideration liabilities and the acquisition-related transaction costs have been classified as acquisition-related expense, net in the condensed consolidated statements of income for the three and six month periods ended November 30, 2015 and 2014 .

Accounts Receivable, net

Accounts Receivable, net	6 Months Ended
Accounts Receivable, net	Nov. 30, 2015
Receivables [Abstract]
Accounts Receivable, net	Accounts Receivable, net Accounts receivable consisted of the following: November 30, 2015 May 31, 2015 Trade accounts receivable $ 152,545 $ 136,208 Allowance for doubtful accounts (3,372 ) (2,980 ) Accounts receivable, net $ 149,173 $ 133,228

Property, Plant and Equipment,

Property, Plant and Equipment, net	6 Months Ended
Property, Plant and Equipment, net	Nov. 30, 2015
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) November 30, 2015 May 31, 2015 Land $ 1,911 $ 1,856 Buildings and improvements 30-40 18,988 17,712 Office furniture and equipment 5-8 8,547 8,084 Machinery and equipment 5-7 164,980 162,612 194,426 190,264 Accumulated depreciation and amortization (117,997 ) (111,008 ) Property, plant and equipment, net $ 76,429 $ 79,256 Depreciation expense for the three months ended November 30, 2015 and 2014 was $5.5 million and $5.5 million , respectively. Depreciation expense for the six months ended November 30, 2015 and 2014 was $11.1 million and $10.9 million , respectively.

Intangible Assets

Intangible Assets	6 Months Ended
Intangible Assets	Nov. 30, 2015
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Intangible Assets	Intangible Assets The gross amount, accumulated amortization and net carrying amount of intangible assets are as follows: November 30, 2015 May 31, 2015 Useful Life (Years) Gross Amount Accumulated Amortization Net Carrying Amount Gross Amount Accumulated Amortization Net Carrying Amount Customer relationships 5-12 $ 80,198 $ (44,040 ) $ 36,158 $ 81,101 $ (41,009 ) $ 40,092 Software/Technology 3-15 16,692 (11,023 ) 5,669 15,738 (10,290 ) 5,448 Covenants not to compete 2-5 11,639 (9,027 ) 2,612 11,678 (8,605 ) 3,073 Other 2-5 6,848 (4,528 ) 2,320 6,910 (4,247 ) 2,663 Total $ 115,377 $ (68,618 ) $ 46,759 $ 115,427 $ (64,151 ) $ 51,276 Amortization expense for the three months ended November 30, 2015 and 2014 was $2.4 million and $2.9 million , respectively. Amortization expense for the six months ended November 30, 2015 and 2014 was $4.8 million and $5.8 million , respectively.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	6 Months Ended
Accrued Expenses and Other Current Liabilities	Nov. 30, 2015
Payables and Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consist of the following: November 30, 2015 May 31, 2015 Accrued salaries, wages and related employee benefits $ 28,231 $ 26,053 Contingent consideration, current portion 2,982 3,543 Accrued workers’ compensation and health benefits 7,135 3,630 Deferred revenue 3,591 3,841 Other accrued expenses 16,994 18,847 Total accrued expenses and other liabilities $ 58,933 $ 55,914

Long-Term Debt

Long-Term Debt	6 Months Ended
Long-Term Debt	Nov. 30, 2015
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt Long-term debt consists of the following: November 30, 2015 May 31, 2015 Senior credit facility $ 84,923 $ 83,062 Notes payable 10,889 24,933 Other 5,906 5,464 Total debt 101,718 113,459 Less: Current portion (13,772 ) (17,902 ) Long-term debt, net of current portion $ 87,946 $ 95,557 Senior Credit Facility On October 31, 2014, the Company entered into a Third Amendment and Modification Agreement, to its revolving line of credit, the Third Amended and Restated Credit Agreement (“Credit Agreement”) with Bank of America, N.A., as agent for the lenders and a lender, and JPMorgan Chase Bank, N.A., Keybank, National Association and TD Bank, N.A., as lenders. The Credit Agreement provides the Company’s with a $175.0 million revolving line of credit, which, under certain circumstances the line of credit 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 November 30, 2015 , the Company had borrowings of $84.9 million and a total of $4.5 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 generally 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 means 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 November 30, 2015 , 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 through fiscal 2015 , the Company issued subordinated notes payable to the sellers. The maturity of the notes that remain outstanding range from two to five years from the date of acquisition with stated interest rates ranging from 0% to 4% . The Company has discounted these obligations to reflect a 2% to 4% market interest. Unamortized discount on the notes was de minimis as of November 30, 2015 and May 31, 2015 . Amortization is recorded as interest expense in the consolidated statements of income. 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

Fair Value Measurements	6 Months Ended
Fair Value Measurements	Nov. 30, 2015
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. It also establishes a three level hierarchy that prioritizes the inputs used to measure fair value. The three levels of the hierarchy are defined as follows: Level 1 — Inputs are unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2 — Observable inputs other than quoted prices included in Level 1, including quoted prices for similar assets or liabilities in active markets, quoted prices for identical assets or liabilities in inactive markets, inputs other than quoted prices that are observable for the asset or liability and inputs derived principally from or corroborated by observable market data. Level 3 — Unobservable inputs reflecting the Company’s own assumptions about inputs that market participants would use in pricing the asset or liability based on the best information available. In accordance with the fair value hierarchy described above, the following table shows the fair value of the Company’s financial liabilities that are required to be remeasured at fair value on a recurring basis: November 30, 2015 Level 1 Level 2 Level 3 Total Liabilities: Contingent consideration $ — $ — $ 5,664 $ 5,664 Total Liabilities $ — $ — $ 5,664 $ 5,664 May 31, 2015 Level 1 Level 2 Level 3 Total Liabilities: Contingent consideration $ — $ — $ 6,411 $ 6,411 Total Liabilities $ — $ — $ 6,411 $ 6,411 The fair value of contingent consideration liabilities that was classified as Level 3 in the table above 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.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
Commitments and Contingencies	Nov. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Litigation and Government Investigations The Company is subject to periodic lawsuits, investigations and claims that arise in the ordinary course of business. Although the Company cannot predict with certainty the ultimate resolution of lawsuits, investigations and claims asserted against it, 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, except for the proceedings described below for which the Company is currently unable to determine the likely outcome or reasonably estimate the amount or range of potential liability estimate. The costs of defense and amounts that may be recovered against the Company in such matters may be covered by insurance, except that the primary claims set forth in the purported class action case in California is excluded from insurance coverage. Litigation and Commercial Claims In April 2015, two separate lawsuits were filed in California as purported class action lawsuits on behalf of current and former Mistras employees. The cases are David Kruger v Mistras Group, Inc. , filed in the U.S. District Court for the Eastern District of California and Edgar Viceral v Mistras Group, et al , pending in the U.S. District Court for the Northern District of California. Both cases were originally filed in California state court and were removed to the respective U.S. District Courts for the districts in which the state court cases were filed. These two cases have been consolidated, with Kruger dismissing his case and joining the Viceral case. As part of this consolidation, the claims in the Kruger case that were not part of the Viceral case were added to the Viceral case by the filing of an amended complaint. The consolidated case alleges violations of California statutes primarily, the California Labor Code, and seeks to proceed as a collective action under the U.S. Fair Labor Standards Act. The case is predicated on claims for allegedly missed rest and meal periods, inaccurate wage statements, and failure to pay all wages due, as well as related unfair business practices, and is requesting payment of all damages, including unpaid wages, and various fines and penalties available under California law. The case is in the preliminary stages. The Company is currently unable to determine the likely outcome or reasonably estimate the amount or range of potential liability, if any, related to these matters, and accordingly, has not established any reserves for these matters. During fiscal 2012 and 2013, the Company performed radiography work on the construction of pipeline projects in the U.S. The Company has received notice that the owner of the pipeline projects contends that certain of the x-ray images the Company’s technicians prepared regarding the projects did not meet the code quality interpretation standards required by API (American Petroleum Institute) 1103. The projects' owner is claiming damages as a result of the alleged quality defects of the Company’s x-ray images. No lawsuit has been filed at this time. The Company is currently unable to determine the likely outcome or reasonably estimate the amount or range of potential liability related to this matter, and accordingly, has not established any reserves for this matter. 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 reserves for this matter. In January 2012, the Company received notice of a governmental investigation concerning an environmental incident which occurred in February 2011 outside on the premises of the Cudahy facility. No human injury or property damage was reported or appears to have been caused as a result of this incident. While management cannot predict the ultimate outcome of this matter, based on its internal investigation to date, the Company does not believe the outcome will have a material effect on its financial condition or results of operations. To the Company’s knowledge, this matter has been dormant since fiscal 2012. Acquisition-related contingencies The Company is liable for contingent consideration in connection with certain of its acquisitions. As of November 30, 2015 , total potential acquisition-related contingent consideration ranged from zero to approximately $20.0 million and would be payable upon the achievement of specific performance metrics by certain of the acquired companies over the next 3.6 years of operations. See Note 4 - Acquisitions to these consolidated financial statements for further discussion of the Company’s acquisitions.

Segment Disclosure

Segment Disclosure	6 Months Ended
Segment Disclosure	Nov. 30, 2015
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 and engineering services that are used to evaluate 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. Allocations for general corporate services, including accounting, audit, and contract management, 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: Three months ended November 30, Six months ended November 30, 2015 2014 2015 2014 Revenues Services $ 150,463 $ 160,874 $ 287,868 $ 282,806 International 38,425 41,018 75,284 81,056 Products and Systems 7,791 7,495 16,477 14,062 Corporate and eliminations (1,893 ) (2,494 ) (4,990 ) (4,458 ) $ 194,786 $ 206,893 $ 374,639 $ 373,466 Three months ended November 30, Six months ended November 30, 2015 2014 2015 2014 Gross profit Services $ 41,118 $ 44,252 $ 77,687 $ 74,023 International 12,106 11,309 22,886 20,777 Products and Systems 3,833 3,328 7,755 5,992 Corporate and eliminations (132 ) 150 (129 ) 241 $ 56,925 $ 59,039 $ 108,199 $ 101,033 Three months ended November 30, Six months ended November 30, 2015 2014 2015 2014 Income (loss) from operations Services $ 18,815 $ 20,071 $ 34,214 $ 28,951 International 3,971 3,177 5,789 2,478 Products and Systems 1,055 417 2,239 (16 ) Corporate and eliminations (4,272 ) (5,473 ) (9,741 ) (9,557 ) $ 19,569 $ 18,192 $ 32,501 $ 21,856 Income (loss) by operating segment includes intercompany transactions, which are eliminated in Corporate and eliminations. Three months ended November 30, Six months ended November 30, 2015 2014 2015 2014 Depreciation and amortization Services $ 5,562 $ 5,579 $ 11,084 $ 10,964 International 1,914 2,050 3,886 4,211 Products and Systems 577 605 1,140 1,201 Corporate and eliminations (90 ) 152 (187 ) 289 $ 7,963 $ 8,386 $ 15,923 $ 16,665 November 30, 2015 May 31, 2015 Goodwill Services $ 119,326 $ 117,279 International 35,126 35,938 Products and Systems 13,197 13,197 $ 167,649 $ 166,414 November 30, 2015 May 31, 2015 Total assets Services $ 307,250 $ 301,031 International 128,460 126,643 Products and Systems 32,614 35,464 Corporate and eliminations 11,740 8,589 $ 480,064 $ 471,727 Revenues by geographic area for the three and six months ended November 30, 2015 and 2014 , respectively, were as follows: Three months ended November 30, Six months ended November 30, 2015 2014 2015 2014 Revenues United States $ 132,068 $ 140,308 $ 262,411 $ 252,248 Other Americas 23,557 25,266 35,086 39,564 Europe 36,468 38,081 71,352 74,726 Asia-Pacific 2,693 3,238 5,790 6,928 $ 194,786 $ 206,893 $ 374,639 $ 373,466

Description of Business and B19

Description of Business and Basis of Presentation (Policies)	6 Months Ended
	Nov. 30, 2015
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 May 31, 2016 and 2015 . Reference to a fiscal year means the fiscal year ended May 31 . 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 consolidated financial statements contained in the Company’s Annual Report on Form 10-K (“Annual Report”) for fiscal 2015 , as filed with the Securities and Exchange Commission on August 12, 2015 .
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 noncontrolling interests are reported in stockholders’ equity in the accompanying consolidated balance sheets. The noncontrolling interests in net income, net of tax, is classified separately in the accompanying consolidated statements of income. All significant intercompany accounts and transactions have been eliminated in consolidation. Mistras Group, Inc.’s and its subsidiaries’ fiscal years end on May 31 except for the subsidiaries in the International segment, which end on April 30. Accordingly, the Company’s International segment subsidiaries are consolidated on a one month lag. Therefore, in the quarter and year of acquisition, results of acquired subsidiaries in the International segment are generally included in consolidated results for one less month than the actual number of months from the acquisition date to the end of the reporting period. Management does not believe that any events occurred during the one-month lag period that would have a material effect on the Company’s consolidated financial statements.
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 May 2014, the Financial Accounting Standards Board ("FASB") issued ASU No. 2014-09, Revenue from Contracts with Customers , which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The ASU will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The new standard is effective for fiscal years and interim periods within those fiscal years beginning December 15, 2017, as a result of a one year deferral in the standard issued by the FASB in August 2015 with ASU 2015-14, Revenue from Contracts with Customers - Deferral of the Effective Date. Early application is not permitted. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures. In February 2015, the FASB issued ASU No. 2015-02, Consolidation (Topic 810): Amendments to the Consolidations Analysis , which changes the guidance for evaluating whether to consolidate certain legal entities. Specifically, the amendments modify the evaluation of whether limited partnerships and similar legal entities are variable interest entities ("VIEs") or voting interest entities. Further, the amendments eliminate the presumption that a general partner should consolidate a limited partnership, as well as affect the consolidation analysis of reporting entities that are involved with VIEs, particularly those that have fee arrangements and related party relationships. The updated guidance is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2015. Early adoption is permitted. The Company does not expect this update to have a material impact on the consolidated financial statements and related disclosures. In September 2015, the FASB issued ASU No. 2015-16, Business Combinations (Topic 805): Simplifying the Accounting for Measurement-Period Adjustments. This amendment will simplify the accounting for adjustments made to provisional amounts recognized in a business combination and eliminates the requirement to retrospectively account for those adjustments in previous reporting periods. This update will require on the face of the income statement or in the notes to the financial statements the amount recorded in current-period earnings that would have previously been recorded if the adjustment to the provisional amounts had been recognized as of the acquisition date. ASU 2015-16 is effective for fiscal years, and interim periods within those fiscal years beginning after December 15, 2015. This update should be applied prospectively and earlier adoption is permitted for financial statements that have not been issued. The Company is evaluating the effect that ASU 2015-16 will have on its consolidated financial statements and related disclosures. 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 is evaluating the effect that ASU 2015-17 will have on its consolidated financial statements and related disclosures
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. It also establishes a three level hierarchy that prioritizes the inputs used to measure fair value. The three levels of the hierarchy are defined as follows: Level 1 — Inputs are unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2 — Observable inputs other than quoted prices included in Level 1, including quoted prices for similar assets or liabilities in active markets, quoted prices for identical assets or liabilities in inactive markets, inputs other than quoted prices that are observable for the asset or liability and inputs derived principally from or corroborated by observable market data. Level 3 — Unobservable inputs reflecting the Company’s own assumptions about inputs that market participants would use in pricing the asset or liability based on the best information available.

Description of Business and B20

Description of Business and Basis of Presentation (Tables)	6 Months Ended
Description of Business and Basis of Presentation (Tables)	Nov. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Quantifying Prior Year Misstatement Corrected in Current Year Financial Statements	In accordance with the SEC Staff Accounting Bulletin (SAB) No. 99, Materiality, and SAB No. 108, Considering the Effects of Prior Year Misstatements when Quantifying Misstatements in Current Year Financial Statements, management evaluated the materiality of the errors from qualitative and quantitative perspectives, and concluded that the errors were immaterial. Accordingly, management has corrected the presentation of the affected line items of the accompanying consolidated statement of cash flows for the six-months ended November 30, 2014, as summarized below. These changes did not impact the Company’s net income, balance sheet, or stockholders’ equity for any period previously reported. Previously Reported Revised Cash flows from operating activities Fair value adjustment to contingent consideration liabilities (808 ) (1,546 ) Accounts payable (666 ) (972 ) Accrued expenses and other current liabilities (3,041 ) (2,074 ) Net cash provided by operating activities 3,230 3,153 Cash flows from investing activities Acquisition of businesses, net of cash acquired (32,967 ) (32,661 ) Net cash used in investing activities (40,666 ) (40,360 ) Cash flows from financing activities Proceeds from long-term debt — 872 Repayment of long-term debt (9,854 ) (10,726 ) Net borrowings against revolver 62,648 63,300 Net cash provided by financing activities 46,810 47,462 Effect of exchange rate changes on cash and cash equivalents 205 (676 )

Earnings per Share (Tables)

Earnings per Share (Tables)	6 Months Ended
Earnings per Share (Tables)	Nov. 30, 2015
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 November 30, Six months ended November 30, 2015 2014 2015 2014 Basic earnings per share Numerator: Net income attributable to Mistras Group, Inc. $ 11,425 $ 10,427 $ 18,297 $ 12,093 Denominator: Weighted average common shares outstanding 28,869 28,619 28,796 28,547 Basic earnings per share $ 0.40 $ 0.36 $ 0.64 $ 0.42 Diluted earnings per share: Numerator: Net income attributable to Mistras Group, Inc. $ 11,425 $ 10,427 $ 18,297 $ 12,093 Denominator: Weighted average common shares outstanding 28,869 28,619 28,796 28,547 Dilutive effect of stock options outstanding 592 675 610 763 Dilutive effect of restricted stock units outstanding 133 103 235 241 29,594 29,397 29,641 29,551 Diluted earnings per share $ 0.39 $ 0.35 $ 0.62 $ 0.41

Acquisitions Acquisitions (Tabl

Acquisitions Acquisitions (Tables)	6 Months Ended
Acquisitions Acquisitions (Tables)	Nov. 30, 2015
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: Fiscal 2016 Number of Entities 1 Consideration transferred: Cash paid $ 1,750 Contingent consideration 945 Consideration transferred 2,695 Current assets 145 Property, plant and equipment 485 Goodwill 2,658 Current liabilities (521 ) Long-term deferred tax liability (72 ) Net assets acquired $ 2,695

Accounts Receivable, net (Table

Accounts Receivable, net (Tables)	6 Months Ended
Accounts Receivable, net (Tables)	Nov. 30, 2015
Receivables [Abstract]
Schedule of accounts receivable	Accounts receivable consisted of the following: November 30, 2015 May 31, 2015 Trade accounts receivable $ 152,545 $ 136,208 Allowance for doubtful accounts (3,372 ) (2,980 ) Accounts receivable, net $ 149,173 $ 133,228

Property, Plant and Equipment24

Property, Plant and Equipment, net (Tables)	6 Months Ended
Property, Plant and Equipment, net (Tables)	Nov. 30, 2015
Property, Plant and Equipment [Abstract]
Schedule of Property, plant and equipment	Property, plant and equipment consisted of the following: Useful Life (Years) November 30, 2015 May 31, 2015 Land $ 1,911 $ 1,856 Buildings and improvements 30-40 18,988 17,712 Office furniture and equipment 5-8 8,547 8,084 Machinery and equipment 5-7 164,980 162,612 194,426 190,264 Accumulated depreciation and amortization (117,997 ) (111,008 ) Property, plant and equipment, net $ 76,429 $ 79,256

Intangible Assets (Tables)

Intangible Assets (Tables)	6 Months Ended
Intangible Assets (Tables)	Nov. 30, 2015
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 are as follows: November 30, 2015 May 31, 2015 Useful Life (Years) Gross Amount Accumulated Amortization Net Carrying Amount Gross Amount Accumulated Amortization Net Carrying Amount Customer relationships 5-12 $ 80,198 $ (44,040 ) $ 36,158 $ 81,101 $ (41,009 ) $ 40,092 Software/Technology 3-15 16,692 (11,023 ) 5,669 15,738 (10,290 ) 5,448 Covenants not to compete 2-5 11,639 (9,027 ) 2,612 11,678 (8,605 ) 3,073 Other 2-5 6,848 (4,528 ) 2,320 6,910 (4,247 ) 2,663 Total $ 115,377 $ (68,618 ) $ 46,759 $ 115,427 $ (64,151 ) $ 51,276

Accrued Expenses and Other Cu26

Accrued Expenses and Other Current Liabilities (Tables)	6 Months Ended
Accrued Expenses and Other Current Liabilities (Tables)	Nov. 30, 2015
Payables and Accruals [Abstract]
Schedule of accrued expenses and other current liabilities	Accrued expenses and other current liabilities consist of the following: November 30, 2015 May 31, 2015 Accrued salaries, wages and related employee benefits $ 28,231 $ 26,053 Contingent consideration, current portion 2,982 3,543 Accrued workers’ compensation and health benefits 7,135 3,630 Deferred revenue 3,591 3,841 Other accrued expenses 16,994 18,847 Total accrued expenses and other liabilities $ 58,933 $ 55,914

Long-Term Debt (Tables)

Long-Term Debt (Tables)	6 Months Ended
Long-Term Debt (Tables)	Nov. 30, 2015
Debt Disclosure [Abstract]
Schedule of long-term debt	Long-term debt consists of the following: November 30, 2015 May 31, 2015 Senior credit facility $ 84,923 $ 83,062 Notes payable 10,889 24,933 Other 5,906 5,464 Total debt 101,718 113,459 Less: Current portion (13,772 ) (17,902 ) Long-term debt, net of current portion $ 87,946 $ 95,557

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
Fair Value Measurements (Tables)	Nov. 30, 2015
Fair Value Disclosures [Abstract]
Schedule of fair value of the Company's financial liabilities that are required to be remeasured at fair value on a recurring basis	In accordance with the fair value hierarchy described above, the following table shows the fair value of the Company’s financial liabilities that are required to be remeasured at fair value on a recurring basis: November 30, 2015 Level 1 Level 2 Level 3 Total Liabilities: Contingent consideration $ — $ — $ 5,664 $ 5,664 Total Liabilities $ — $ — $ 5,664 $ 5,664 May 31, 2015 Level 1 Level 2 Level 3 Total Liabilities: Contingent consideration $ — $ — $ 6,411 $ 6,411 Total Liabilities $ — $ — $ 6,411 $ 6,411

Segment Disclosure (Tables)

Segment Disclosure (Tables)	6 Months Ended
Segment Disclosure (Tables)	Nov. 30, 2015
Segment Reporting [Abstract]
Schedule of consolidated financial information by segment	Selected consolidated financial information by segment for the periods shown was as follows: Three months ended November 30, Six months ended November 30, 2015 2014 2015 2014 Revenues Services $ 150,463 $ 160,874 $ 287,868 $ 282,806 International 38,425 41,018 75,284 81,056 Products and Systems 7,791 7,495 16,477 14,062 Corporate and eliminations (1,893 ) (2,494 ) (4,990 ) (4,458 ) $ 194,786 $ 206,893 $ 374,639 $ 373,466 Three months ended November 30, Six months ended November 30, 2015 2014 2015 2014 Gross profit Services $ 41,118 $ 44,252 $ 77,687 $ 74,023 International 12,106 11,309 22,886 20,777 Products and Systems 3,833 3,328 7,755 5,992 Corporate and eliminations (132 ) 150 (129 ) 241 $ 56,925 $ 59,039 $ 108,199 $ 101,033 Three months ended November 30, Six months ended November 30, 2015 2014 2015 2014 Income (loss) from operations Services $ 18,815 $ 20,071 $ 34,214 $ 28,951 International 3,971 3,177 5,789 2,478 Products and Systems 1,055 417 2,239 (16 ) Corporate and eliminations (4,272 ) (5,473 ) (9,741 ) (9,557 ) $ 19,569 $ 18,192 $ 32,501 $ 21,856 Income (loss) by operating segment includes intercompany transactions, which are eliminated in Corporate and eliminations. Three months ended November 30, Six months ended November 30, 2015 2014 2015 2014 Depreciation and amortization Services $ 5,562 $ 5,579 $ 11,084 $ 10,964 International 1,914 2,050 3,886 4,211 Products and Systems 577 605 1,140 1,201 Corporate and eliminations (90 ) 152 (187 ) 289 $ 7,963 $ 8,386 $ 15,923 $ 16,665 November 30, 2015 May 31, 2015 Goodwill Services $ 119,326 $ 117,279 International 35,126 35,938 Products and Systems 13,197 13,197 $ 167,649 $ 166,414 November 30, 2015 May 31, 2015 Total assets Services $ 307,250 $ 301,031 International 128,460 126,643 Products and Systems 32,614 35,464 Corporate and eliminations 11,740 8,589 $ 480,064 $ 471,727
Schedule of revenues by geographic area	Revenues by geographic area for the three and six months ended November 30, 2015 and 2014 , respectively, were as follows: Three months ended November 30, Six months ended November 30, 2015 2014 2015 2014 Revenues United States $ 132,068 $ 140,308 $ 262,411 $ 252,248 Other Americas 23,557 25,266 35,086 39,564 Europe 36,468 38,081 71,352 74,726 Asia-Pacific 2,693 3,238 5,790 6,928 $ 194,786 $ 206,893 $ 374,639 $ 373,466

Description of Business and B30

Description of Business and Basis of Presentation - Principles of Consolidation (Details)	6 Months Ended
	Nov. 30, 2015mo
Principles of Consolidation
Period lag in the consolidation of International segment subsidiaries	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	1

Description of Business and B31

Description of Business and Basis of Presentation - Immaterial Correction (Details) - USD ($) $ in Thousands	6 Months Ended
	Nov. 30, 2015	Nov. 30, 2014
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Fair value adjustment to contingent consideration liabilities	$ (1,068)	$ (1,546)
Accounts payable	(1,248)	(972)
Accrued expenses and other current liabilities	5,226	(2,074)
Net cash provided by operating activities	26,524	3,153
Acquisition of businesses, net of cash acquired	(1,709)	(32,661)
Net cash used in investing activities	(9,623)	(40,360)
Proceeds from borrowings of long-term debt	1,968	872
Repayment of long-term debt	(15,870)	(10,726)
Net borrowings against revolver		63,300
Net cash provided by financing activities	(16,644)	47,462
Effect of exchange rate changes on cash and cash equivalents	$ (233)	(676)
Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Fair value adjustment to contingent consideration liabilities		(808)
Accounts payable		(666)
Accrued expenses and other current liabilities		(3,041)
Net cash provided by operating activities		3,230
Acquisition of businesses, net of cash acquired		(32,967)
Net cash used in investing activities		(40,666)
Proceeds from borrowings of long-term debt		0
Repayment of long-term debt		(9,854)
Net borrowings against revolver		62,648
Net cash provided by financing activities		46,810
Effect of exchange rate changes on cash and cash equivalents		$ 205

Share-Based Compensation - Stoc

Share-Based Compensation - Stock Options (Details) $ in Millions	3 Months Ended		6 Months Ended
	Nov. 30, 2015USD ($)shares	Nov. 30, 2014USD ($)	Nov. 30, 2015USD ($)planshares	Nov. 30, 2014USD ($)shares
Share-based compensation
Number of employee stock ownership plans \| plan			2
Stock Options
Share-based compensation
Recognized share-based compensation expense (less than) \| $	$ 0.1	$ 0.1	$ 0.1	$ 0.1
Unrecognized compensation costs, net of estimated forfeitures (less than) \| $	$ 0.1		$ 0.1
Weighted-average period over which unrecognized compensation cost is expected to be recognized			3 months
Stock options granted (in shares) \| shares			0	0
2007 Plan
Share-based compensation
Number of awards that may be granted (in shares) \| shares	0		0

Share-Based Compensation - Rest

Share-Based Compensation - Restricted Stock Unit Awards (Details) shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Nov. 30, 2015USD ($)	Nov. 30, 2014USD ($)	Nov. 30, 2015USD ($)directorshares	Nov. 30, 2014USD ($)directorshares
Restricted Stock Units
Share-based compensation
Recognized share-based compensation expense	$ 1.1	$ 1.2	$ 2.2	$ 2.3
Unrecognized compensation cost, net of estimated forfeitures	9.5		$ 9.5
Weighted-average period over which unrecognized compensation cost is expected to be recognized			2 years 7 months 2 days
Fair value of shares vested			$ 3.4	$ 4.9
Shares vested (in shares) \| shares			217	226
Restricted Stock Units \| Non-employee directors
Share-based compensation
Number of fully vested common stock granted \| shares			15	10
Number of non-employee directors to whom fully vested common stock is granted \| director			5	5
Fair value of shares vested			$ 0.2	$ 0.2
Fiscal 2015 Grants \| Performance Shares [Member]
Share-based compensation
Recognized share-based compensation expense	$ 0	$ 0	$ 0.2	$ 0.1

Share-Based Compensation - Perf

Share-Based Compensation - Performance Restricted Stock Units (Details) shares in Thousands, $ in Millions	3 Months Ended			6 Months Ended
	Nov. 30, 2015USD ($)performance_metricshares	Aug. 31, 2015shares	Nov. 30, 2014USD ($)	Nov. 30, 2015USD ($)shares	Nov. 30, 2014USD ($)
Performance Shares [Member] \| Fiscal 2016 Grants
Share-based compensation
Requisite service period	5 years
Performance period	1 year
Number of performance award metrics \| performance_metric	3
Recognized share-based compensation expense	$ 0.2			$ 0.2
Unrecognized compensation cost	$ 3.8			$ 3.8
Weighted-average period over which unrecognized compensation cost is expected to be recognized				4 years 1 month 2 days
Performance Shares [Member] \| Fiscal 2016 Grants \| Executive and Senior Officers [Member]
Share-based compensation
Number of shares granted in period \| shares	80	154
Nonvested shares outstanding \| shares	234			234
Performance Shares [Member] \| Fiscal 2015 Grants
Share-based compensation
Recognized share-based compensation expense	$ 0		$ 0	$ 0.2	$ 0.1
Performance Shares [Member] \| Fiscal 2014 Grants
Share-based compensation
Recognized share-based compensation expense	$ 0		$ 0.8	$ 0.4	$ 1.6
Performance Restricted Stock Units with one year EPS performance condition \| Fiscal 2014 Grants
Share-based compensation
Performance period				1 year
Performance Restricted Stock Units with two year EPS performance condition \| Fiscal 2014 Grants
Share-based compensation
Performance period				2 years
Performance Restricted Stock Units with three year EPS performance condition
Share-based compensation
Performance period				3 years
Performance Restricted Stock Units with three year EPS performance condition \| Fiscal 2014 Grants
Share-based compensation
Performance period				3 years

Earnings per Share (Details)

Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2015	Nov. 30, 2014
Basic earnings per share
Net income attributable to Mistras Group, Inc.	$ 11,425	$ 10,427	$ 18,297	$ 12,093
Denominator:
Weighted average common shares outstanding (in shares)	28,869	28,619	28,796	28,547
Basic earnings per share (in dollars per share)	$ 0.40	$ 0.36	$ 0.64	$ 0.42
Denominator:
Weighted average common shares outstanding (in shares)	28,869	28,619	28,796	28,547
Dilutive effect of stock options outstanding (in shares)	592	675	610	763
Dilutive effect of restricted stock units outstanding (in shares)	133	103	235	241
Weighted average common shares outstanding, diluted (in shares)	29,594	29,397	29,641	29,551
Diluted earnings per share (in dollars per share)	$ 0.39	$ 0.35	$ 0.62	$ 0.41

Acquisitions - Acquisitions (De

Acquisitions - Acquisitions (Details)	3 Months Ended	6 Months Ended
Acquisitions - Acquisitions (Details)	Nov. 30, 2014USD ($)Entity	Nov. 30, 2015USD ($)Entity	May. 31, 2015USD ($)	Aug. 31, 2014USD ($)
Acquisitions
Contingent consideration		$ 5,664,000	$ 6,411,000
Goodwill		$ 167,649,000	166,414,000
Period over which potential acquisition-related contingent consideration would be payable		3 years 7 months
Fair value of contingent consideration liabilities (less than)		$ 5,664,000	$ 6,411,000
Fiscal 2015 Acquisitions
Acquisitions
Number of Entities \| Entity	3
Cash paid	$ 34,000,000
Goodwill				$ 43,900,000
Notes payable issued as part of acquisition	$ 22,700,000
Fiscal 2015 Acquisitions \| Minimum
Acquisitions
Amortization period of intangible assets acquired	3 years
Fiscal 2015 Acquisitions \| Maximum
Acquisitions
Amortization period of intangible assets acquired	10 years
United States \| Fiscal 2016 Acquisitions
Acquisitions
Number of Entities \| Entity		1
Cash paid		$ 1,750,000
Contingent consideration		945,000
Consideration transferred		2,695,000
Current assets		145,000
Property, plant and equipment		485,000
Goodwill		2,658,000
Current liabilities		(521,000)
Long-term deferred tax liability		(72,000)
Net assets acquired		2,695,000
Fair value of contingent consideration liabilities (less than)		$ 945,000
United States \| Fiscal 2015 Acquisitions
Acquisitions
Percentage of common stock acquired	100.00%			100.00%
Quebec \| Fiscal 2015 Acquisitions
Acquisitions
Contingent consideration				$ 2,700,000
Period over which potential acquisition-related contingent consideration would be payable	3 years
Fair value of contingent consideration liabilities (less than)				$ 2,700,000

Acquisitions - Acquisition-Rela

Acquisitions - Acquisition-Related Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2015	Nov. 30, 2014	May. 31, 2015
Acquisitions
Net decrease of acquisition-related contingent consideration liabilities			$ 1,068	$ 1,546
Acquisition related costs (less than)	$ 100	$ 200	100	200
Contingent consideration	5,664		5,664		$ 6,411
Fiscal 2016 Acquisitions
Acquisitions
Net decrease of acquisition-related contingent consideration liabilities	$ (200)		$ (1,050)
Fiscal 2015 Acquisitions
Acquisitions
Net decrease of acquisition-related contingent consideration liabilities		$ (600)		$ (1,598)

Accounts Receivable, net (Detai

Accounts Receivable, net (Details) - USD ($) $ in Thousands	Nov. 30, 2015	May. 31, 2015
Receivables [Abstract]
Trade accounts receivable	$ 152,545	$ 136,208
Allowance for doubtful accounts	(3,372)	(2,980)
Accounts receivable, net	$ 149,173	$ 133,228

Property, Plant and Equipment39

Property, Plant and Equipment, net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2015	Nov. 30, 2014	May. 31, 2015
Property, Plant and Equipment, net
Property, plant and equipment, gross	$ 194,426		$ 194,426		$ 190,264
Accumulated depreciation and amortization	(117,997)		(117,997)		(111,008)
Property, plant and equipment, net	76,429		76,429		79,256
Depreciation expense	5,500	$ 5,500	11,100	$ 10,900
Land
Property, Plant and Equipment, net
Property, plant and equipment, gross	1,911		1,911		1,856
Buildings and improvements
Property, Plant and Equipment, net
Property, plant and equipment, gross	18,988		$ 18,988		17,712
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	8,547		$ 8,547		8,084
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	$ 164,980		$ 164,980		$ 162,612
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

Intangible Assets (Details)

Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Intangible Assets (Details) - USD ($) $ in Thousands	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2015	Nov. 30, 2014	May. 31, 2015
Intangible assets
Gross Amount	$ 115,377		$ 115,377		$ 115,427
Accumulated Amortization	(68,618)		(68,618)		(64,151)
Net Carrying Amount	46,759		46,759		51,276
Amortization expense	2,400	$ 2,900	4,800	$ 5,800
Customer relationships
Intangible assets
Gross Amount	80,198		80,198		81,101
Accumulated Amortization	(44,040)		(44,040)		(41,009)
Net Carrying Amount	36,158		$ 36,158		40,092
Customer relationships \| Minimum
Intangible assets
Useful Life (Years)			5 years
Customer relationships \| Maximum
Intangible assets
Useful Life (Years)			12 years
Software/Technology
Intangible assets
Gross Amount	16,692		$ 16,692		15,738
Accumulated Amortization	(11,023)		(11,023)		(10,290)
Net Carrying Amount	5,669		$ 5,669		5,448
Software/Technology \| Minimum
Intangible assets
Useful Life (Years)			3 years
Software/Technology \| Maximum
Intangible assets
Useful Life (Years)			15 years
Covenants not to compete
Intangible assets
Gross Amount	11,639		$ 11,639		11,678
Accumulated Amortization	(9,027)		(9,027)		(8,605)
Net Carrying Amount	2,612		$ 2,612		3,073
Covenants not to compete \| Minimum
Intangible assets
Useful Life (Years)			2 years
Covenants not to compete \| Maximum
Intangible assets
Useful Life (Years)			5 years
Other
Intangible assets
Gross Amount	6,848		$ 6,848		6,910
Accumulated Amortization	(4,528)		(4,528)		(4,247)
Net Carrying Amount	$ 2,320		$ 2,320		$ 2,663
Other \| Minimum
Intangible assets
Useful Life (Years)			2 years
Other \| Maximum
Intangible assets
Useful Life (Years)			5 years

Accrued Expenses and Other Cu41

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Nov. 30, 2015	May. 31, 2015
Payables and Accruals [Abstract]
Accrued salaries, wages and related employee benefits	$ 28,231	$ 26,053
Contingent consideration, current portion	2,982	3,543
Accrued workers’ compensation and health benefits	7,135	3,630
Deferred revenue	3,591	3,841
Other accrued expenses	16,994	18,847
Total accrued expenses and other liabilities	$ 58,933	$ 55,914

Long-Term Debt - Schedule of Lo

Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	Nov. 30, 2015	May. 31, 2015
Debt Instrument [Line Items]
Long-term debt	$ 101,718	$ 113,459
Less: Current portion	(13,772)	(17,902)
Long-term debt, net of current portion	87,946	95,557
Senior credit facility
Debt Instrument [Line Items]
Long-term debt	84,923	83,062
Notes payable
Debt Instrument [Line Items]
Long-term debt	10,889	24,933
Other
Debt Instrument [Line Items]
Long-term debt	$ 5,906	$ 5,464

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Details)	Oct. 31, 2014USD ($)Quarter	Nov. 30, 2015USD ($)
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		$ 84,900,000
Outstanding letters of credit		$ 4,500,000
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, minimum (as a percent)		0.00%
Interest rate, maximum (as a percent)		4.00%
Notes payable \| Minimum
Notes Payable and Other
Maturity term from the date of acquisition		2 years
Market interest rate (as a percent)		2.00%
Notes payable \| Maximum
Notes Payable and Other
Maturity term from the date of acquisition		5 years
Market interest rate (as a percent)		4.00%

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands	Nov. 30, 2015	May. 31, 2015
Liabilities:
Contingent consideration	$ 5,664	$ 6,411
Recurring basis
Liabilities:
Contingent consideration	5,664	6,411
Total Liabilities	5,664	6,411
Recurring basis \| Level 1
Liabilities:
Contingent consideration	0	0
Total Liabilities	0	0
Recurring basis \| Level 2
Liabilities:
Contingent consideration	0	0
Total Liabilities	0	0
Recurring basis \| Level 3
Liabilities:
Contingent consideration	5,664	6,411
Total Liabilities	$ 5,664	$ 6,411

Commitments and Contingencies (

Commitments and Contingencies (Details)	1 Months Ended	6 Months Ended
Commitments and Contingencies (Details)	Apr. 30, 2015claim	Nov. 30, 2015USD ($)claim
Litigation
Period over which potential acquisition-related contingent consideration would be payable		3 years 7 months
Uninsured risk
Litigation
Number of claims filed \| claim	2
Lawsuits for alleged quality defects
Litigation
Number of claims filed \| claim		0
Acquisition-related contingencies
Litigation
Potential acquisition-related contingent consideration, low end of range \| $		$ 0
Potential acquisition-related contingent consideration, high end of range \| $		$ 20,000,000

Segment Disclosure - Financial

Segment Disclosure - Financial Information by Segment (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2015USD ($)	Nov. 30, 2014USD ($)	Nov. 30, 2015USD ($)segment	Nov. 30, 2014USD ($)	May. 31, 2015USD ($)
Segment Reporting [Abstract]
Number of operating segments \| segment			3
Financial information by segment
Revenues	$ 194,786	$ 206,893	$ 374,639	$ 373,466
Gross profit	56,925	59,039	108,199	101,033
Income (loss) from operations	19,569	18,192	32,501	21,856
Depreciation and amortization	7,963	8,386	15,923	16,665
Goodwill	167,649		167,649		$ 166,414
Total assets	480,064		480,064		471,727
Corporate and eliminations
Financial information by segment
Revenues	(1,893)	(2,494)	(4,990)	(4,458)
Gross profit	(132)	150	(129)	241
Income (loss) from operations	(4,272)	(5,473)	(9,741)	(9,557)
Depreciation and amortization	(90)	152	(187)	289
Total assets	11,740		11,740		8,589
Services \| Operating segments
Financial information by segment
Revenues	150,463	160,874	287,868	282,806
Gross profit	41,118	44,252	77,687	74,023
Income (loss) from operations	18,815	20,071	34,214	28,951
Depreciation and amortization	5,562	5,579	11,084	10,964
Goodwill	119,326		119,326		117,279
Total assets	307,250		307,250		301,031
International \| Operating segments
Financial information by segment
Revenues	38,425	41,018	75,284	81,056
Gross profit	12,106	11,309	22,886	20,777
Income (loss) from operations	3,971	3,177	5,789	2,478
Depreciation and amortization	1,914	2,050	3,886	4,211
Goodwill	35,126		35,126		35,938
Total assets	128,460		128,460		126,643
Products and Systems \| Operating segments
Financial information by segment
Revenues	7,791	7,495	16,477	14,062
Gross profit	3,833	3,328	7,755	5,992
Income (loss) from operations	1,055	417	2,239	(16)
Depreciation and amortization	577	$ 605	1,140	$ 1,201
Goodwill	13,197		13,197		13,197
Total assets	$ 32,614		$ 32,614		$ 35,464

Segment Disclosure - Revenues b

Segment Disclosure - Revenues by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2015	Nov. 30, 2014
Revenue and long-lived assets by geographic area
Revenues	$ 194,786	$ 206,893	$ 374,639	$ 373,466
United States
Revenue and long-lived assets by geographic area
Revenues	132,068	140,308	262,411	252,248
Other Americas
Revenue and long-lived assets by geographic area
Revenues	23,557	25,266	35,086	39,564
Europe
Revenue and long-lived assets by geographic area
Revenues	36,468	38,081	71,352	74,726
Asia-Pacific
Revenue and long-lived assets by geographic area
Revenues	$ 2,693	$ 3,238	$ 5,790	$ 6,928