Neogen (NEOG) 10-K 30 Jul 14 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	31-May-14	Jun. 30, 2014	Nov. 30, 2013
Document Information [Line Items]	'	'	'
Document Type	'10-K	'	'
Amendment Flag	'false	'	'
Document Period End Date	31-May-14	'	'
Document Fiscal Year Focus	'2014	'	'
Document Fiscal Period Focus	'FY	'	'
Trading Symbol	'NEOG	'	'
Entity Registrant Name	'NEOGEN CORP	'	'
Entity Central Index Key	'0000711377	'	'
Current Fiscal Year End Date	'--05-31	'	'
Entity Well-known Seasoned Issuer	'Yes	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Filer Category	'Large Accelerated Filer	'	'
Entity Common Stock, Shares Outstanding	'	36,734,222	'
Entity Public Float	'	'	$1,862,000,000

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	31-May-14	31-May-13
In Thousands, unless otherwise specified
Current Assets	'	'
Cash and cash equivalents	$40,675	$50,032
Marketable securities	35,821	35,337
Accounts receivable, less allowance of $1,200 and $900 at May 31, 2014 and 2013	51,901	38,737
Inventories	51,178	38,315
Deferred income taxes	1,710	1,462
Prepaid expenses and other current assets	7,461	4,564
Total Current Assets	188,746	168,447
Property and Equipment	'	'
Land and improvements	1,875	1,669
Buildings and improvements	26,456	22,779
Machinery and equipment	40,333	33,060
Furniture and fixtures	2,282	1,021
Construction in progress	1,659	1,561
Property, Plant and Equipment, Gross, Total	72,605	60,090
Less accumulated depreciation	30,656	25,745
Net Property and Equipment	41,949	34,345
Other Assets	'	'
Goodwill	68,190	59,491
Other non-amortizable intangible assets	9,682	6,660
Amortizable customer based intangible assets, net of accumulated amortization of $11,915 and $9,446 at May 31, 2014 and 2013	25,230	12,345
Other non-current assets, net of accumulated amortization of $5,494 and $4,222 at May 31, 2014 and 2013	11,504	9,270
Total Other Assets	114,606	87,766
Total assets	345,301	290,558
Current Liabilities	'	'
Accounts payable	13,396	9,212
Accruals	'	'
Compensation and benefits	4,357	3,227
Federal income taxes	0	165
Other	7,214	5,115
Total Current Liabilities	24,967	17,719
Deferred Income Taxes	12,155	12,449
Other Long-Term Liabilities	1,879	2,103
Total Liabilities	39,001	32,271
Commitments and Contingencies (note 7)	'	'
Equity	'	'
Preferred stock, $1.00 par value - shares authorized 100,000; none issued and outstanding	0	0
Common stock, $0.16 par value - shares authorized 60,000,000; 36,732,313 and 36,084,021 shares issued and outstanding at May 31, 2014 and 2013	5,877	5,773
Additional paid-in capital	118,070	99,935
Accumulated other comprehensive income (loss)	371	-1,372
Retained earnings	182,043	153,885
Total Neogen Corporation and Subsidiaries Stockholders' Equity	306,361	258,221
Noncontrolling interest	-61	66
Total Equity	306,300	258,287
TOTAL LIABILITIES AND EQUITY	$345,301	$290,558

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	31-May-14	31-May-13
In Thousands, except Share data, unless otherwise specified
Accounts receivable, allowance	$1,200	$900
Customer based intangible assets, accumulated amortization	11,915	9,446
Other non-current assets, accumulated amortization	$5,494	$4,222
Preferred stock, par value	$1	$1
Preferred stock, shares authorized	100,000	100,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$0.16	$0.16
Common stock, shares authorized	60,000,000	60,000,000
Common stock, shares issued	36,732,313	36,084,021
Common stock, shares outstanding	36,732,313	36,084,021

Consolidated_Statements_of_Inc

Consolidated Statements of Income (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	31-May-14	31-May-13	31-May-12
Revenues	'	'	'
Product revenues	$219,734	$184,134	$164,910
Service revenues	27,671	23,394	19,136
Total Revenues	247,405	207,528	184,046
Cost of Revenues	'	'	'
Cost of product revenues	107,167	84,045	78,823
Cost of service revenues	17,640	13,989	12,798
Total Cost of Revenues	124,807	98,034	91,621
Gross Margin	122,598	109,494	92,425
Operating Expenses	'	'	'
Sales and marketing	46,432	40,791	35,026
General and administrative	24,449	20,216	17,024
Research and development	8,326	7,781	6,636
Operating Expenses, Total	79,207	68,788	58,686
Operating Income	43,391	40,706	33,739
Other Income (Expense)	'	'	'
Interest income	115	144	107
Royalty income	231	364	329
Change in purchase consideration	38	-14	154
Other, net	-744	-59	-490
Nonoperating Income (Expense), Total	-360	435	100
Income Before Income Taxes	43,031	41,141	33,839
Provision for Income Taxes	15,000	14,100	11,450
Net Income	28,031	27,041	22,389
Net Loss Attributable to Noncontrolling Interest	127	149	124
Net Income Attributable to Neogen	$28,158	$27,190	$22,513
Net Income Attributable to Neogen Per Share	'	'	'
Basic	$0.77	$0.76	$0.64
Diluted	$0.76	$0.75	$0.62

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-12
Net income	$28,031	$27,041	$22,389
Other Comprehensive Income (Loss), Net of Tax:	'	'	'
Currency Translation Adjustments	1,743	-145	-833
Other Comprehensive Income (Loss)	1,743	-145	-833
Comprehensive Income	29,774	26,896	21,556
Comprehensive Loss Attributable to Noncontrolling Interest	127	149	124
Comprehensive Income Attributable to Neogen Corporation	$29,901	$27,045	$21,680

Consolidated_Statements_of_Equ

Consolidated Statements of Equity (USD $)	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Noncontrolling Interest
In Thousands, except Share data
Beginning Balance at May. 31, 2011	$189,102	$5,589	$79,386	($394)	$104,182	$339
Beginning Balance (in shares) at May. 31, 2011	'	34,935,905	'	'	'	'
Exercise of options and warrants, including share based compensation and income tax benefit (in shares)	'	472,520	'	'	'	'
Exercise of options and warrants, including share based compensation and income tax benefit	7,887	76	7,811	'	'	'
Issuance of shares under Employee Stock Purchase Plan (in shares)	21,216	21,216	'	'	'	'
Issuance of shares under Employee Stock Purchase Plan	509	3	506	'	'	'
Net income (loss)	22,389	'	'	'	22,513	-124
Other comprehensive income (loss)	-833	'	'	-833	'	'
Ending Balance at May. 31, 2012	219,054	5,668	87,703	-1,227	126,695	215
Ending Balance (in shares) at May. 31, 2012	'	35,429,641	'	'	'	'
Exercise of options and warrants, including share based compensation and income tax benefit (in shares)	'	631,992	'	'	'	'
Exercise of options and warrants, including share based compensation and income tax benefit	11,801	101	11,700	'	'	'
Issuance of shares under Employee Stock Purchase Plan (in shares)	22,388	22,388	'	'	'	'
Issuance of shares under Employee Stock Purchase Plan	536	4	532	'	'	'
Net income (loss)	27,041	'	'	'	27,190	-149
Other comprehensive income (loss)	-145	'	'	-145	'	'
Ending Balance at May. 31, 2013	258,287	5,773	99,935	-1,372	153,885	66
Ending Balance (in shares) at May. 31, 2013	36,084,021	36,084,021	'	'	'	'
Exercise of options and warrants, including share based compensation and income tax benefit (in shares)	'	629,826	'	'	'	'
Exercise of options and warrants, including share based compensation and income tax benefit	17,623	101	17,522	'	'	'
Issuance of shares under Employee Stock Purchase Plan (in shares)	18,466	18,466	'	'	'	'
Issuance of shares under Employee Stock Purchase Plan	616	3	613	'	'	'
Net income (loss)	28,031	'	'	'	28,158	-127
Other comprehensive income (loss)	1,743	'	'	1,743	'	'
Ending Balance at May. 31, 2014	$306,300	$5,877	$118,070	$371	$182,043	($61)
Ending Balance (in shares) at May. 31, 2014	36,732,313	36,732,313	'	'	'	'

Consolidated_Statements_of_Equ1

Consolidated Statements of Equity (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-12
Exercise of options and warrants including share based compensation, income tax benefit	$4,757	$3,113	$1,829

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-12
Net income	$28,031	$27,041	$22,389
Adjustments to reconcile net income to net cash provided from operating activities:	'	'	'
Depreciation and amortization	9,180	7,411	6,173
Deferred income taxes	-542	287	1,340
Share based compensation	3,686	3,064	2,455
Excess income tax benefit from the exercise of stock options	-4,757	-3,113	-1,829
Changes in operating assets and liabilities, net of business acquisitions:	'	'	'
Accounts receivable	-10,602	-2,674	-7,204
Inventories	-3,529	-2,082	-3,093
Prepaid expenses and other current assets	-2,654	-1,505	1,497
Accounts payable	1,970	-1,417	2,330
Accruals and other changes	885	-451	-1,781
Net Cash From Operating Activities	21,668	26,561	22,277
Cash Flows Used In Investing Activities	'	'	'
Purchases of property, equipment and other noncurrent assets	-11,543	-8,897	-12,413
Proceeds from the sale of marketable securities	91,207	67,039	72,270
Purchases of marketable securities	-91,691	-82,776	-71,631
Business acquisitions, net of cash acquired	-39,265	-13,318	-4,011
Net Cash Used In Investing Activities	-51,292	-37,952	-15,785
Cash Flows From Financing Activities	'	'	'
Exercise of stock options	14,851	9,533	5,797
Excess income tax benefit from the exercise of stock options	4,757	3,113	1,829
Decrease in other long-term liabilities	0	-155	-750
Net Cash From Financing Activities	19,608	12,491	6,876
Effect of Exchange Rate on Cash	659	-113	-167
Net Increase (Decrease) In Cash and Cash Equivalents	-9,357	987	13,201
Cash And Cash Equivalents At Beginning of Year	50,032	49,045	35,844
Cash And Cash Equivalents At End of Year	40,675	50,032	49,045
Supplementary Cash Flow Information	'	'	'
Income taxes paid, net of refunds	$9,956	$8,986	$6,445

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	31-May-14
Summary of Significant Accounting Policies	'
	1	Summary of Significant Accounting Policies
	Nature of Operations
	Neogen Corporation develops, manufactures, and markets a diverse line of products and services dedicated to food and animal safety.
	Basis of Consolidation
	The consolidated financial statements include the accounts of Neogen Corporation and its subsidiaries (collectively, the Company), all of which are wholly owned, with the exception of Neogen Latinoamerica S.A.P.I. DE C.V. and Neogen do Brasil, which are both 90% owned as of May 31, 2014. The Company made an additional capital contribution on December 31, 2013 which increased its ownership interest in Neogen Latinoamerica from 60% to 90%. Noncontrolling interest represents the noncontrolling owner’s proportionate share in the equity of the Company’s majority owned subsidiaries. The noncontrolling owner’s proportionate share in the income or losses of the Company’s majority owned subsidiaries is subtracted from or added to, net income to calculate the net income attributable to Neogen Corporation.
	All intercompany accounts and transactions have been eliminated in consolidation.
	Share and per share amounts reflect the October 30, 2013 3-for-2 stock split as if it took place at the beginning of the periods presented.
	Use of Estimates
	The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from these estimates.
	Comprehensive Income
	Comprehensive income represents net income and any revenues, expenses, gains and losses that, under U.S. generally accepted accounting principles, are excluded from net income and recognized directly as a component of equity. Accumulated other comprehensive income (loss) consists solely of foreign currency translation adjustments.
	Accounts Receivable and Concentrations of Credit Risk
	Financial instruments which potentially subject the Company to concentrations of credit risk consist principally of accounts receivable. Management attempts to minimize credit risk by reviewing customers’ credit history before extending credit and by monitoring credit exposure on a regular basis. An allowance for doubtful accounts on accounts receivable is established based upon factors surrounding the credit risk of specific customers, historical trends and other information. Collateral or other security is generally not required for accounts receivable. Once a receivable balance has been determined to be uncollectible, that amount is written off to the allowance for doubtful accounts. No customer accounted for more than 10% of accounts receivable at May 31, 2014. The activity in the allowance for doubtful accounts was as follows:
			Year ended May 31
	(In Thousands)		2014			2013			2012
	Beginning Balance		$	900		$	800		$	800
	Provision			367			193			91
	Recoveries			8			24			12
	Write-offs			(75	)		(117	)		(103	)
	Ending Balance		$	1,200		$	900		$	800
	Fair Value of Financial Instruments
	The carrying amounts of the Company’s financial instruments other than cash equivalents and marketable securities, which include accounts receivable and accounts payable, approximate fair value based on either their short maturity or current terms for similar instruments.
	Fair Value Measurements
	Fair value measurements are determined based upon the exit price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants exclusive of any transaction costs. The Company utilizes a fair value hierarchy based upon the observability of inputs used in valuation techniques as follows:
	Level 1:		Observable inputs such as quoted prices in active markets;
	Level 2:		Inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and
	Level 3:		Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own         assumptions.
	Cash and Cash Equivalents
	Cash and cash equivalents consist of bank demand accounts, savings deposits, certificates of deposit and commercial paper with original maturities of 90 days or less. Cash and cash equivalents were $40,675,000 and $50,032,000 at May 31, 2014 and 2013, respectively. The carrying value of these assets approximates fair value due to the short maturity of these instruments and meet the Level 1 criteria.
	Marketable Securities
	The Company has marketable securities held by banks or broker-dealers consisting of short-term domestic certificates of deposit of $17,576,000 and commercial paper rated at least A-2/P-2 with maturities between 91 days and one year of $18,245,000. Outstanding marketable securities at May 31, 2014 were $35,821,000; there were $35,337,000 marketable securities outstanding at May 31, 2013. These securities are classified as available for sale. The primary objective of the Company’s short-term investment activity is to preserve capital for the purpose of funding operations, capital expenditures and business acquisitions; short-term investments are not entered into for trading or speculative purposes. These securities are recorded at fair value (that approximate cost) based on recent trades or pricing models and therefore meet the Level 2 criteria. Interest income on these investments is recorded within Other Income on the income statement.
	Inventories
	Inventories are stated at the lower of cost, determined on the first-in, first-out method, or market. The components of inventories were as follows:
			May 31
	(In thousands)		2014			2013
	Raw materials		$	21,515		$	16,587
	Work-in-process			3,681			3,583
	Finished and purchased finished goods			25,982			18,145
			$	51,178		$	38,315
	The Company’s inventories are analyzed for slow moving and obsolete items no less frequently than quarterly and the valuation allowance is adjusted as required. The valuation allowance for inventory was $1,425,000 and $1,250,000 at May 31, 2014 and 2013, respectively.
	Property and Equipment
	Property and equipment is stated at cost. Expenditures for major improvements are capitalized while repairs and maintenance are charged to expense. Depreciation is provided on the straight-line method over the estimated useful lives of the respective assets, which are generally seven to 39 years for buildings and improvements and three to ten years for furniture, fixtures, machinery and equipment. Depreciation expense was $5,383,000, $4,417,000 and $3,646,000 in fiscal years 2014, 2013 and 2012, respectively.
	Goodwill and Other Intangible Assets
	Goodwill represents the excess of purchase price over fair value of tangible net assets of acquired businesses after amounts are allocated to other identifiable intangible assets. Other intangible assets include customer relationships, trademarks, licenses, trade names, covenants not-to-compete and patents. Amortizable intangible assets are amortized on either an accelerated or a straight-line basis over five to 20 years. The Company reviews the carrying amounts of goodwill and other non-amortizable intangible assets annually, or when indications of impairment exist, to determine if such assets may be impaired. If the Company’s qualitative assessment concludes that it is more likely than not that an impairment exists, or the Company skips the qualitative assessment, then the Company performs a quantitative assessment. If the carrying amounts of these assets are deemed to be less than fair value based upon a discounted cash flow analysis and comparison to comparable EBITDA multiples of peer companies, such assets are reduced to their estimated fair value and a charge is made to operations. The remaining weighted-average amortization period for customer-based intangibles and other intangibles are both 12 years, respectively, at May 31, 2014 and May 31, 2013.
	Long-lived Assets
	Management reviews the carrying values of its long-lived assets to be held and used, including definite-lived intangible assets, for possible impairment whenever events or changes in business conditions warrant such a review. The carrying value of a long-lived asset is considered impaired when the anticipated separately identifiable undiscounted cash flows over the remaining useful life of the asset are less than the carrying value of the asset. In such an event, fair value is determined using discounted cash flows and if lower than the carrying value, impairment is recognized through a charge to operations.
	Reclassifications
	Certain amounts in the fiscal 2013 and 2012 financial statements have been reclassified to conform to the fiscal 2014 presentation.
	Stock Options
	At May 31, 2014, the Company had stock option plans which are described more fully in Note 5.
	The weighted-average fair value per share of stock options granted during fiscal years 2014, 2013 and 2012, estimated on the date of grant using the Black-Scholes option pricing model, was $9.87, $9.21 and $6.94, respectively. The fair value of stock options granted was estimated using the following weighted-average assumptions:
			Year ended May 31
			2014			2013			2012
	Risk-free interest rate			0.80%			1.20%			1.20%
	Expected dividend yield			0%			0%			0%
	Expected stock price volatility			33.10%			39.20%			36.40%
	Expected option life			4.0 years			4.0 years			4.0 years
	The risk-free interest rate for periods within the expected life of options granted is based on the United States Treasury yield curve in effect at the time of grant. Expected stock price volatility is based on historical volatility of the Company’s stock. The expected option life, representing the period of time that options granted are expected to be outstanding, is based on historical option exercise and employee termination data. The Company recognizes the fair value of stock options using the accelerated method over their requisite service periods which the Company has determined to be the vesting periods.
	Revenue Recognition
	Revenue from products and services is recognized when the product has been shipped or the service has been performed, the sales price is fixed and determinable, and collection of any resulting receivable is probable. To the extent customer payment is received before all recognition criteria has been met, these revenues are initially deferred and later recognized in the period that all recognition criteria has been met. Where right of return exists, allowances are made at the time of sale to reflect expected returns based on historical experience.
	Shipping and Handling Costs
	Shipping and handling costs that are charged to and reimbursed by the customer are recognized as revenues, while the related expenses incurred by the Company are recorded in sales and marketing expense; these expenses totaled $7,472,000, $6,856,000 and $5,940,000 in fiscal years 2014, 2013 and 2012, respectively.
	Income Taxes
The Company accounts for income taxes using the asset and liability method. Under this method, deferred income tax assets and liabilities are determined based on differences between the financial reporting and tax bases of assets and liabilities and for tax credit carry forwards and are measured using the enacted tax rates in effect for the years in which the differences are expected to reverse. Deferred income tax expense represents the change in net deferred income tax assets and liabilities during the year.
The Company’s foreign subsidiaries are comprised of Neogen Europe (wholly-owned subsidiary), Neogen Latinoamerica (90% owned subsidiary), Neogen do Brasil (90% owned subsidiary) and Neogen China (wholly-owned subsidiary). Based on historical experience, as well as the Company’s future plans, earnings from these subsidiaries are expected to be re-invested indefinitely for future expansion and working capital needs. Furthermore, the Company’s domestic operations have historically produced sufficient operating cash flow to mitigate the need to remit foreign earnings. On an annual basis, the Company evaluates the current business environment and whether any new events or other external changes might require a re-evaluation of the decision to indefinitely re-invest foreign earnings. At May 31, 2014, unremitted earnings of the foreign subsidiaries were $18,262,000.
Research and Development Costs
Research and development costs are expensed as incurred.
Advertising Costs
Advertising costs are expensed as incurred and totaled $1,344,000, $1,055,000 and $1,001,000 in fiscal years 2014, 2013 and 2012, respectively.
Net Income Attributable to Neogen per Share
Basic net income per share is based on the weighted average number of common shares outstanding during each year. Diluted earnings per share is based on the weighted average number of common shares and dilutive potential common shares outstanding. The Company’s dilutive potential common shares outstanding during the years result entirely from dilutive stock options. The following table presents the net income per share calculations:
		Year ended May 31
(in thousands, except per share)		2014			2013			2012
Numerator for basic and diluted net income per share - Net income attributable to Neogen		$	28,158		$	27,190		$	22,513
Denominator - Denominator for basic net income per share weighted average shares			36,511			35,768			35,199
Effect of dilutive stock options			756			723			830
Denominator for diluted net income per share			37,267			36,491			36,029
Net income attributable to Neogen per share
Basic		$	0.77		$	0.76		$	0.64
Diluted		$	0.76		$	0.75		$	0.62
At May 31, 2014, 2013 and 2012, 48,716, 88,912 and 78,450 shares, respectively, were excluded from the computations of diluted net income per share, as the option exercise prices exceeded the average market price of the common shares.
On October 30, 2013, the Company paid a 3-for-2 stock split effected in the form of a dividend of its common stock. All share and per share amounts, with the exception of par value per share, have been adjusted to reflect the stock split as if it had taken place at the beginning of the period presented. The common stock and additional paid-in-capital accounts at May 31, 2013 and 2012 reflect the retroactive capitalization of the 3-for-2 stock split.
New Accounting Pronouncements
In February 2013, the Financial Accounting Standards Board (FASB) further amended ASC 220, Comprehensive Income, with ASU 2013-02, Comprehensive Income (Topic 220) – Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income (amended ASC 220), which was designed to improve the reporting of reclassifications out of accumulated other comprehensive income by requiring an entity to present the effect of significant reclassifications out of accumulated other comprehensive income on the respective lines of net income. The impact of adopting amended ASC 220 did not have a material impact on the consolidated financial statements.
In May 2014, the FASB issued a new standard on revenue recognition. The new standard outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. The core principle of the revenue model is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard is designed to create greater comparability for financial statement users across industries and jurisdictions and also requires enhanced disclosures. The guidance is effective for fiscal years, and interim periods within those years, beginning after December 15, 2016. Early adoption is not permitted. The Company is currently evaluating the impact of the adoption of this standard on its consolidated financial statements.

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	12 Months Ended
	31-May-14
Goodwill and Other Intangible Assets	'
	2	Goodwill and Other Intangible Assets
	Management has completed the annual impairment analysis of goodwill and intangible assets with indefinite lives using a quantitative assessment as of the first day of the fourth quarter of fiscal years 2014, 2013 and 2012, respectively, and determined that recorded amounts were not impaired and that no write-down was necessary.
	The following table summarizes goodwill by reportable segment:
	(In thousands)		Food Safety		Animal Safety		Total
	Balance, May 31, 2012		$	16,696	$	36,356	$	53,052
	Goodwill acquired			0		6,439		6,439
	Balance, May 31, 2013		$	16,696	$	42,795	$	59,491
	Goodwill acquired			0		8,699		8,699
	Balance, May 31, 2014		$	16,696	$	51,494	$	68,190
	At May 31, 2014, non-amortizable intangible assets included licenses of $569,000, trademarks of $7,889,000 and other intangibles of $1,224,000. At May 31, 2013, non-amortizable intangible assets included licenses of $569,000, trademarks of $4,867,000 and other intangibles of $1,224,000.
	Amortizable intangible assets consisted of the following and are included in customer based intangible and other noncurrent assets within the consolidated balance sheets:
	(In thousands)		Gross		Less		Net
			Carrying		Accumulated		Carrying
			Amount		Amortization		Amount
	Licenses		$	6,701	$	1,873	$	4,828
	Covenants not to compete			474		256		218
	Patents			5,990		2,746		3,244
	Customer relationship intangibles			37,145		11,915		25,230
	Other product and service related intangibles			3,833		619		3,214
	Balance, May 31, 2014		$	54,143	$	17,409	$	36,734
	Licenses		$	4,165	$	1,409	$	2,756
	Covenants not to compete			334		186		148
	Patents			5,184		2,363		2,821
	Customer relationship intangibles			21,791		9,446		12,345
	Other product and service-related intangibles			3,809		264		3,545
	Balance, May 31, 2013		$	35,283	$	13,668	$	21,615
	Amortization expense for intangibles totaled $3,797,000, $2,994,000 and $2,527,000 in fiscal years 2014, 2013, and 2012, respectively. The estimated amortization expense for each of the five succeeding fiscal years is as follows: $4,158,000 in 2015, $3,916,000 in 2016, $3,770,000 in 2017, $3,552,000 in 2018 and $2,955,000 in 2019. The amortizable intangible assets useful lives are 5 to 20 years for licenses, 5 years for covenants not to compete, 5 to 20 years for patents, and 12 to 20 years for customer relationship intangibles. All definite lived intangibles are amortized on a straight line basis with the exception of definite lived customer relationship intangibles and product and service-related intangibles which are amortized on an accelerated basis.

Business_Combinations

Business Combinations	12 Months Ended
	31-May-14
Business Combinations	'
	3	Business Combinations
	The Consolidated Statements of Income reflect the results of operations for business acquisitions since the respective dates of purchase. All are accounted for using the purchase method. Goodwill recognized in the acquisitions discussed below relates primarily to enhancing the Company’s strategic platform for the expansion of available product offerings.
	On June 21, 2011, the Company acquired the assets of VeroMara seafood testing laboratory for approximately $813,000 in cash and a potential contingent consideration payment of approximately $200,000 from its parent company, GlycoMar Ltd. Formerly based in Oban, Scotland, VeroMara offered commercial testing for the shellfish and salmon aquaculture industries, including tests for shellfish toxins, general foodborne pathogens, including E. coli, noroviruses, and salmon husbandry. The acquisition has been integrated into the Company’s Food Safety segment at its Ayr, Scotland location.
	On May 1, 2012, the Company purchased the assets of the Igenity animal genomics business from Merial Limited. Consideration for the purchase was $3,200,000 in cash and included allocations of net current assets of $110,000, property and equipment of $340,000, $600,000 accrued for contingent consideration, intangible assets of $2,036,000 and the remainder to goodwill (deductible for tax purposes). During 2012, the Company paid $500,000 for data sets included in the contingent consideration. The allocation was generally based on the fair value of these assets determined using the income approach. These fair value measurements were based on significant inputs not observable in the market and thus represent Level 3 fair value measurements. In the past, GeneSeek Inc. (acquired by the Company in 2010) conducted the genetic testing of samples for Igenity, and Igenity used the information with its extensive bioinformatics system to identify the animal’s positive or negative traits. The Igenity business was moved to GeneSeek’s operations in Lincoln, Nebraska, and operates as part of Neogen’s GeneSeek subsidiary, within the Animal Safety segment. In May 2013, the Company reversed the remaining $100,000 of the contingent consideration accrual to Other Income, as the business did not attain the revenue level stipulated for that year.
	On October 1, 2012, the Company acquired all of the stock of Macleod Pharmaceuticals Inc., of Fort Collins, Colorado. Macleod is the manufacturer of Uniprim, a leading veterinary antibiotic. The product is widely distributed throughout the U.S., and is also available in Canada through an exclusive distribution agreement. Consideration for the purchase was $9,918,000 in net cash and $100,000 accrued for contingent consideration. The final purchase price allocation, based upon the fair value of these assets determined using the income approach, included accounts receivable of $353,000, inventory of $1,238,000, property and equipment of $300,000, current liabilities of $82,000, deferred tax liabilities of $2,054,000, contingent consideration payment liabilities of $100,000, intangible assets of $5,542,000 and the remainder to goodwill (non-deductible for tax purposes). These values are Level 3 fair value measurements. Macleod operates as a subsidiary of Neogen Corporation, reporting within the Animal Safety segment. In October 2013, the Company paid $62,000 for contingent consideration; the remaining $38,000 of the accrual was reversed to Other Income.
	On January 2, 2013, the Company acquired the assets of Scidera Genomics LLC, an animal genomics business based in Davis, California. The company, formerly operated as MetaMorphix, Inc., or MMI Genomics, performs parentage testing and trait analysis primarily for the cattle and canine industries. Consideration for the purchase was $3,400,000 in cash. The final purchase price allocation included current assets of $35,000, property and equipment of $246,000, intangible assets of $1,570,000 and the remainder to goodwill (deductible for tax purposes). These values are Level 3 fair value measurements. This business was relocated to the Company’s GeneSeek operation in Lincoln, Nebraska in 2013, and reports within the Animal Safety segment.
	On July 1, 2013, the Company acquired the assets of SyrVet Inc., a veterinary business based in Waukee, Iowa. SyrVet offered a product line similar to Neogen’s Ideal Instruments line of veterinary instruments with a strong presence in Mexico and Latin America. Consideration for the purchase was $10,012,000 in cash and up to $1,500,000 of a contingent consideration liability, due at the end of the first year, based on an excess net sales formula. The Company has estimated the contingent consideration liability to be $930,000, based on forecasted sales. The final purchase price allocation, based upon the fair value of these assets determined using the income approach, included accounts receivable of $747,000, net inventory of $2,195,000, property and equipment of $556,000, current liabilities of $226,000, contingent consideration liabilities of $930,000, non-amortizable trademarks of $790,000, intangible assets of $4,810,000 (with an estimated life of 15 years) and the remainder to goodwill (deductible for tax purposes). These values are Level 3 fair value measurements. This business has been relocated to Lexington, Kentucky and integrated with the Company’s current operations there, reporting within the Animal Safety segment.
	On November 1, 2013, the Company acquired the assets of Prima Tech Incorporated, a veterinary instrument company based in Kenansville, North Carolina. Prima Tech manufactures devices used by farmers, ranchers, and veterinarians to inject animals, provide topical applications, and to use for oral administration. Prima Tech is also a supplier of products used in artificial insemination in the swine industry. Consideration for the purchase was $12,068,000 in cash and up to $600,000 of contingent consideration, due at the end of the first year, based on an excess net sales formula. The Company has estimated the contingent consideration liability to be $146,000 based on forecasted sales. The final purchase price allocation, based upon the fair value of these assets determined using the income approach, included accounts receivable of $963,000, net inventory of $2,796,000, property and equipment of $1,653,000, prepaid assets of $8,000, current liabilities of $1,840,000, contingent consideration liabilities of $146,000, non-amortizable trademarks of $1,500,000, intangible assets of $4,400,000 (with an estimated life of 5-15 years) and the remainder to goodwill (deductible for tax purposes). These values are Level 3 fair value measurements. This business will continue to operate in its current location and reports within the Animal Safety segment.
	On January 2, 2014, the Company acquired all of the stock of Chem-Tech Ltd., a pest control manufacturing and distribution business located in Pleasantville, Iowa. Consideration for the purchase was $17,185,000 in cash and up to $1,000,000 of a contingent consideration liability, due at the end of the first year, based on an excess sales formula. The Company has estimated the contingent consideration liability to be $400,000, based on forecasted sales. The preliminary purchase price allocation included accounts receivable of $380,000, net inventory of $4,096,000, prepaid assets of $225,000, property and equipment of $682,000, current liabilities of $184,000, contingent consideration liabilities of $400,000, non-amortizable trademarks of $662,000, intangible assets of $7,536,000 (with an estimated life of 15 years) and the remainder to goodwill (deductible for tax purposes). These values are Level 3 fair value measurements. This business will continue to operate in its current location and reports within the Animal Safety segment.

LongTerm_Debt

Long-Term Debt	12 Months Ended
	31-May-14
Long-Term Debt	'
	4	Long-Term Debt
	The Company has a financing agreement with a bank providing for an unsecured revolving line of credit of up to $12,000,000 which was amended on May 30, 2014, to extend the maturity from September 1, 2014 to September 1, 2017. There were no advances against this line of credit during fiscal years 2014, 2013 and 2012, and no balance outstanding at May 31, 2014 and 2013. Interest is at LIBOR plus 100 basis points (rate under the terms of the agreement was 1.15% at May 31, 2014). Financial covenants include maintaining specified levels of tangible net worth, debt service coverage, and funded debt to EBITDA, each of which the Company was in compliance with at May 31, 2014 and May 31, 2013.

Equity_Compensation_Plans

Equity Compensation Plans	12 Months Ended
	31-May-14
Equity Compensation Plans	'
	5	Equity Compensation Plans
	Qualified and non-qualified options to purchase shares of common stock may be granted to directors, officers and employees of the Company under the terms of the Company’s stock option plans. These options are granted at an exercise price of not less than the fair market value of the stock on the date of grant. Remaining shares available for grant under stock option plans were 805,000, 1,227,000 and 1,662,000 at May 31, 2014, 2013 and 2012, respectively. Options vest ratably over three and five year periods and the contractual terms are generally five or ten years.
	(Share in thousands)		Shares			Weighted-Average		Weighted-Average
						Exercise Price		Grant Date Fair  Value
	Outstanding at May 31, 2011 (764 exercisable)			2,361		$	11.85	$	3.81
	Granted			474			23.06		6.94
	Exercised			(480	)		8.29		2.93
	Forfeited			(41	)		11.08		3.59
	Outstanding at May 31, 2012 (863 exercisable)			2,314			14.89		4.63
	Granted			459			28.67		9.21
	Exercised			(657	)		10.61		3.43
	Forfeited			(24	)		19.67		6.07
	Outstanding at May 31, 2013 (749 exercisable)			2,092			19.21		6
	Granted			512			36.44		9.87
	Exercised			(643	)		13.69		4.28
	Forfeited			(92	)		22.08		6.65
	Outstanding at May 31, 2014 (577 exercisable)			1,869			25.69		7.62
	The following is a summary of stock options outstanding at May 31, 2014:
	(Options in thousands)
			Options Outstanding							Options Exercisable
	Range of Exercise price		Number			Average Remaining		Weighted-Average		Number		Weighted Average
						Contractual Life		Exercise Price				Exercise Price
						(in years)
	$  5.45 - $ 16.12			286			1.8	$	11.7		201	$	11.14
	16.13 - 22.91			288			2.5		19.32		152		19.57
	22.92 - 28.26			353			2.8		23.17		134		23.28
	28.27 - 32.37			439			4		28.67		90		28.67
	32.38 - 41.65			503			4.9		36.44		—		—
				1,869			3.4		25.69		577		18.91
	The weighted average exercise price of shares that were exercisable at May 31, 2014 and 2013 was $18.91 and $14.21, respectively.
	The aggregate intrinsic value of options outstanding and options exercisable was $22,751,000 and $10,984,000, respectively, at May 31, 2014, $35,778,000 and $16,557,000 respectively, at May 31, 2013 and $25,617,000 and $12,855,000 respectively, at May 31, 2012. The aggregate intrinsic value of options exercised during the year was $17,669,000 in fiscal 2014, $12,519,000 in fiscal 2013 and $8,226,000 in fiscal 2012. Remaining compensation cost to be expensed in future periods for non-vested options was $4,096,000 at May 31, 2013, with a weighted average expense recognition period of 3.2 years.
	Common stock totaling 65,309 of the 337,500 originally authorized shares are reserved for issuance under the terms of the 2002 Employee Stock Purchase Plan. An additional 375,000 shares are also reserved for issuance under the terms of the 2011 Employee Stock Purchase Plan. The plan gives eligible employees the option to purchase common stock at a 5% discount to the lower of the market value of the stock at the beginning or end of each participation period. Total individual purchases in any year are limited to 10% of compensation. Shares purchased by employees were 18,466, 22,388 and 21,216 in fiscal years 2014, 2013 and 2012, respectively.

Income_Taxes

Income Taxes	12 Months Ended
	31-May-14
Income Taxes	'
	6	Income Taxes
	Income before income taxes by source consists of the following amounts:
			Year ended May 31
	(In thousands)		2014			2013			2012
	U.S.		$	37,568		$	37,407		$	31,775
	Foreign			5,463			3,734			2,064
			$	43,031		$	41,141		$	33,839
	The provision for income taxes consisted of the following:
			Year ended May 31
	(In thousands)		2014			2013			2012
	Current:
	U.S. Taxes		$	14,442		$	12,959		$	9,520
	Foreign			1,100			854			587
	Deferred			(542	)		287			1,343
			$	15,000		$	14,100		$	11,450
	The reconciliation of income taxes computed at the U.S. federal statutory tax rate to income tax expense is as follows:
			Year ended May 31
	(In thousands)		2014			2013			2012
	Tax at U.S. statutory rates		$	15,061		$	14,400		$	11,900
	Tax credits and other			(574	)		(980	)		(755	)
	Provisions for state income taxes, net of federal benefit			513			680			305
			$	15,000		$	14,100		$	11,450
	Deferred income taxes reflect the tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Significant components of the Company’s deferred income tax liabilities and assets are as follows:
			May 31
	(In thousands)		2014			2013
	Deferred income tax liabilities
	Indefinite and long-lived assets		$	(13,759	)	$	(13,953	)
	Prepaids			(358	)		(333	)
				(14,117	)		(14,286	)
	Deferred income tax assets
	Inventories and accounts receivable			1,471			1,228
	Accrued liabilities and other			2,201			2,071
				3,672			3,299
	Net deferred income tax liabilities		$	(10,445	)	$	(10,987	)
	At the end of fiscal 2011, the Company was under audit by the Internal Revenue Service for its fiscal 2009 year; in fiscal 2012 this audit was expanded to include the fiscal 2010 year as well. The audit concluded in late fiscal 2012 with a slight favorable adjustment; thus, amounts totaling $550,000 which had been reserved as uncertain tax positions were reversed in the fourth quarter of fiscal 2012, resulting in an effective tax rate of 33.7% for the year. Absent this adjustment, the Company’s fiscal 2012 tax rate would have been 35.5%, compared to 34.3% in fiscal 2013 and 34.9% in fiscal 2014.
	The Company has no significant accrual for unrecognized tax benefits at May 31, 2014. Should the accrual of any interest or penalties relative to unrecognized tax benefits be necessary, such accruals will be reflected within income tax accounts. For the majority of tax jurisdictions, the Company is no longer subject to U.S. Federal, State and local or non U.S. income tax examinations by tax authorities for fiscal years before 2011.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	31-May-14
Commitments and Contingencies	'
	7	Commitments and Contingencies
	The Company is involved in environmental remediation and monitoring activities at its Randolph, Wisconsin manufacturing facility and accrues for related costs when such costs are determined to be probable and estimable. The Company is currently paying annual costs of remediation which have ranged from $47,000 to $79,000 per year over the past five years. The Company’s estimated liability for these costs of $916,000 at May 31, 2014 and 2013, measured on an undiscounted basis over an estimated period of 15 years; $50,000 of the liability is recorded within current liabilities and the remainder is recorded within other long term liabilities in the consolidated balance sheet.
	The Company has agreements with unrelated third parties that provide for the payment of license fees and royalties on the sale of certain products. Royalty expense under the terms of these agreements was $2,278,000, $1,837,000 and $1,371,000 for fiscal years 2014, 2013 and 2012, respectively.
	The Company has agreements with unrelated third parties that provide for guaranteed minimum royalty payments to be paid each fiscal year by the Company for certain technologies, as follows: 2015—$658,000, 2016—$700,000, 2017—$669,000, and 2018—$769,000.
	The Company leases office and manufacturing facilities under noncancelable operating leases. Rent expense for fiscal years 2014, 2013 and 2012 was $856,000, $657,000 and $495,000, respectively. Future fiscal year minimum rental payments for these leases over their remaining terms are as follows: 2015—$470,000, 2016—$324,000, 2017—$130,000, 2018—$74,000 and 2019 and later—$96,000.
	The Company is subject to certain legal and other proceedings in the normal course of business that, in the opinion of management, should not have a material effect on its future results of operations or financial position.

Defined_Contribution_Benefit_P

Defined Contribution Benefit Plan	12 Months Ended
	31-May-14
Defined Contribution Benefit Plan	'
	8	Defined Contribution Benefit Plan
	The Company maintains a defined contribution 401(k) benefit plan covering substantially all employees. Employees are permitted to defer compensation up to IRS limits, with the Company matching 100% of the first 3% of deferred compensation and 50% of the next 2% deferred. The Company’s expense under this plan was $954,000, $863,000 and $760,000 in fiscal years 2014, 2013 and 2012, respectively.

Segment_Information

Segment Information	12 Months Ended
	31-May-14
Segment Information	'
	9	Segment Information
	The Company has two reportable segments: Food Safety and Animal Safety. The Food Safety segment is primarily engaged in the development, production and marketing of diagnostic test kits and related products used by food producers and processors to detect harmful natural toxins, foodborne bacteria, allergens and levels of general sanitation. The Animal Safety segment is primarily engaged in the development, production and marketing of products dedicated to animal safety, including a complete line of consumable products marketed to veterinarians and animal health product distributors; this segment also provides genetic identification and related interpretive bioinformatic services. Additionally, the Animal Safety segment produces and markets rodenticides, disinfectants, and insecticides to assist in control of rodents, insects and disease in and around agricultural, food production and other facilities.
	These segments are managed separately because they represent strategic business units that offer different products and require different marketing strategies. The Company evaluates performance based on total sales and operating income of the respective segments. The accounting policies of each of the segments are the same as those described in Note 1.
	Segment information is as follows:
	(In thousands)		Food Safety		Animal Safety		Corporate and			Total
							Eliminations (1)
	Fiscal 2014
	Product revenues to external customers		$	111,545	$	108,189	$	0		$	219,734
	Service revenues to external customers			4,745		22,926		0			27,671
	Total revenues to external customers			116,290		131,115		0			247,405
	Operating income (loss)			28,009		18,571		(3,189	)		43,391
	Depreciation and amortization			4,181		4,999		0			9,180
	Total assets			105,607		173,643		66,051			345,301
	Expenditures for long-lived assets			5,999		5,544		0			11,543
	Fiscal 2013
	Product revenues to external customers		$	102,971	$	81,163	$	0		$	184,134
	Service revenues to external customers			3,187		20,207		0			23,394
	Total revenues to external customers			106,158		101,370		0			207,528
	Operating income (loss)			27,366		15,858		(2,518	)		40,706
	Depreciation and amortization			3,874		3,537		0			7,411
	Total assets			93,079		121,908		75,571			290,558
	Expenditures for long-lived assets			6,046		2,851		0			8,897
	Fiscal 2012
	Product revenues to external customers		$	90,460	$	74,450	$	0		$	164,910
	Service revenues to external customers			644		18,492		0			19,136
	Total revenues to external customers			91,104		92,942		0			184,046
	Operating income (loss)			23,932		12,039		(2,232	)		33,739
	Depreciation and amortization			3,500		2,673		0			6,173
	Total assets			62,227		106,987		82,386			251,600
	Expenditures for long-lived assets			4,633		7,780		0			12,413
	-1	Includes corporate assets, including cash and cash equivalents, marketable securities, current and deferred tax accounts, and overhead expenses not allocated to specific business segments. Also includes the elimination of intersegment transactions and noncontrolling interests.
	Revenues to customers located outside the United States amounted to $96,111,000 or 38.8% of consolidated revenues in fiscal 2014, $83,171,000 or 40.1% in fiscal 2013 and $76,672,000 or 41.7% in fiscal 2012 and were derived primarily in various countries throughout Europe, Canada, and the geographic areas of South and Central America and Asia. No customer represented revenues in excess of 10% of consolidated net sales in any of the three years. The United States based operations represent 95% of the Company’s long-lived assets as of May 31, 2014 and 95% as May 31, 2013.

Stock_Repurchase

Stock Repurchase	12 Months Ended
	31-May-14
Stock Repurchase	'
	10	Stock Repurchase
	In December 2008, the Company’s Board of Directors authorized a program to purchase, subject to market conditions, up to 1,125,000 shares of the Company’s common stock. As of May 31, 2014, 112,026 cumulative shares have been purchased in negotiated and open market transactions for a total price, including commissions, of approximately $923,000. There were no purchases in fiscal years 2014 or 2013. Shares purchased under the program were retired.

Summary_of_Quarterly_Data_Unau

Summary of Quarterly Data (Unaudited)	12 Months Ended
	31-May-14
Summary of Quarterly Data (Unaudited)	'
	11	Summary of Quarterly Data (Unaudited)
			Quarter Ended
	(In thousands, except per share)		August		November		February		May
			2013		2013		2014		2014
	Total revenues		$	58,548	$	59,599	$	61,996	$	67,262
	Gross margin			30,364		29,491		30,705		32,038
	Net income attributable to Neogen			7,839		6,207		6,575		7,537
	Basic net income per share			0.22		0.17		0.18		0.2
	Diluted net income per share			0.21		0.17		0.18		0.2
			Quarter Ended
	(In thousands, except per share)		August		November		February		May
			2012		2012		2013		2013
	Total revenues		$	49,729	$	50,737	$	51,055	$	56,007
	Gross margin			26,494		27,306		27,313		28,381
	Net income attributable to Neogen			6,714		6,793		6,652		7,031
	Basic net income per share			0.19		0.19		0.19		0.19
	Diluted net income per share			0.19		0.18		0.19		0.19
	Quarterly net income per share is based on weighted-average shares outstanding and potentially dilutive stock options for the specific period, and as a result, will not necessarily aggregate to total net income per share as computed for the year as disclosed in the consolidated statements of income.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	31-May-14
Nature of Operations	'
	Nature of Operations
	Neogen Corporation develops, manufactures, and markets a diverse line of products and services dedicated to food and animal safety.
Basis of Consolidation	'
	Basis of Consolidation
	The consolidated financial statements include the accounts of Neogen Corporation and its subsidiaries (collectively, the Company), all of which are wholly owned, with the exception of Neogen Latinoamerica S.A.P.I. DE C.V. and Neogen do Brasil, which are both 90% owned as of May 31, 2014. The Company made an additional capital contribution on December 31, 2013 which increased its ownership interest in Neogen Latinoamerica from 60% to 90%. Noncontrolling interest represents the noncontrolling owner’s proportionate share in the equity of the Company’s majority owned subsidiaries. The noncontrolling owner’s proportionate share in the income or losses of the Company’s majority owned subsidiaries is subtracted from or added to, net income to calculate the net income attributable to Neogen Corporation.
	All intercompany accounts and transactions have been eliminated in consolidation.
	Share and per share amounts reflect the October 30, 2013 3-for-2 stock split as if it took place at the beginning of the periods presented.
Use of Estimates	'
	Use of Estimates
	The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from these estimates.
Comprehensive Income	'
	Comprehensive Income
	Comprehensive income represents net income and any revenues, expenses, gains and losses that, under U.S. generally accepted accounting principles, are excluded from net income and recognized directly as a component of equity. Accumulated other comprehensive income (loss) consists solely of foreign currency translation adjustments.
Accounts Receivable and Concentrations of Credit Risk	'
	Accounts Receivable and Concentrations of Credit Risk
	Financial instruments which potentially subject the Company to concentrations of credit risk consist principally of accounts receivable. Management attempts to minimize credit risk by reviewing customers’ credit history before extending credit and by monitoring credit exposure on a regular basis. An allowance for doubtful accounts on accounts receivable is established based upon factors surrounding the credit risk of specific customers, historical trends and other information. Collateral or other security is generally not required for accounts receivable. Once a receivable balance has been determined to be uncollectible, that amount is written off to the allowance for doubtful accounts. No customer accounted for more than 10% of accounts receivable at May 31, 2014. The activity in the allowance for doubtful accounts was as follows:
		Year ended May 31
	(In Thousands)	2014			2013			2012
	Beginning Balance	$	900		$	800		$	800
	Provision		367			193			91
	Recoveries		8			24			12
	Write-offs		(75	)		(117	)		(103	)
	Ending Balance	$	1,200		$	900		$	800
Fair Value of Financial Instruments	'
	Fair Value of Financial Instruments
	The carrying amounts of the Company’s financial instruments other than cash equivalents and marketable securities, which include accounts receivable and accounts payable, approximate fair value based on either their short maturity or current terms for similar instruments.
Fair Value Measurements	'
	Fair Value Measurements
	Fair value measurements are determined based upon the exit price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants exclusive of any transaction costs. The Company utilizes a fair value hierarchy based upon the observability of inputs used in valuation techniques as follows:
	Level 1:	Observable inputs such as quoted prices in active markets;
	Level 2:	Inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and
	Level 3:	Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own         assumptions.
Cash and Cash Equivalents	'
	Cash and Cash Equivalents
	Cash and cash equivalents consist of bank demand accounts, savings deposits, certificates of deposit and commercial paper with original maturities of 90 days or less. Cash and cash equivalents were $40,675,000 and $50,032,000 at May 31, 2014 and 2013, respectively. The carrying value of these assets approximates fair value due to the short maturity of these instruments and meet the Level 1 criteria.
Marketable Securities	'
	Marketable Securities
	The Company has marketable securities held by banks or broker-dealers consisting of short-term domestic certificates of deposit of $17,576,000 and commercial paper rated at least A-2/P-2 with maturities between 91 days and one year of $18,245,000. Outstanding marketable securities at May 31, 2014 were $35,821,000; there were $35,337,000 marketable securities outstanding at May 31, 2013. These securities are classified as available for sale. The primary objective of the Company’s short-term investment activity is to preserve capital for the purpose of funding operations, capital expenditures and business acquisitions; short-term investments are not entered into for trading or speculative purposes. These securities are recorded at fair value (that approximate cost) based on recent trades or pricing models and therefore meet the Level 2 criteria. Interest income on these investments is recorded within Other Income on the income statement.
Inventories	'
	Inventories
	Inventories are stated at the lower of cost, determined on the first-in, first-out method, or market. The components of inventories were as follows:
		May 31
	(In thousands)	2014			2013
	Raw materials	$	21,515		$	16,587
	Work-in-process		3,681			3,583
	Finished and purchased finished goods		25,982			18,145
		$	51,178		$	38,315
	The Company’s inventories are analyzed for slow moving and obsolete items no less frequently than quarterly and the valuation allowance is adjusted as required. The valuation allowance for inventory was $1,425,000 and $1,250,000 at May 31, 2014 and 2013, respectively.
Property and Equipment	'
	Property and Equipment
	Property and equipment is stated at cost. Expenditures for major improvements are capitalized while repairs and maintenance are charged to expense. Depreciation is provided on the straight-line method over the estimated useful lives of the respective assets, which are generally seven to 39 years for buildings and improvements and three to ten years for furniture, fixtures, machinery and equipment. Depreciation expense was $5,383,000, $4,417,000 and $3,646,000 in fiscal years 2014, 2013 and 2012, respectively.
Goodwill and Other Intangible Assets	'
	Goodwill and Other Intangible Assets
	Goodwill represents the excess of purchase price over fair value of tangible net assets of acquired businesses after amounts are allocated to other identifiable intangible assets. Other intangible assets include customer relationships, trademarks, licenses, trade names, covenants not-to-compete and patents. Amortizable intangible assets are amortized on either an accelerated or a straight-line basis over five to 20 years. The Company reviews the carrying amounts of goodwill and other non-amortizable intangible assets annually, or when indications of impairment exist, to determine if such assets may be impaired. If the Company’s qualitative assessment concludes that it is more likely than not that an impairment exists, or the Company skips the qualitative assessment, then the Company performs a quantitative assessment. If the carrying amounts of these assets are deemed to be less than fair value based upon a discounted cash flow analysis and comparison to comparable EBITDA multiples of peer companies, such assets are reduced to their estimated fair value and a charge is made to operations. The remaining weighted-average amortization period for customer-based intangibles and other intangibles are both 12 years, respectively, at May 31, 2014 and May 31, 2013.
Long-lived Assets	'
	Long-lived Assets
	Management reviews the carrying values of its long-lived assets to be held and used, including definite-lived intangible assets, for possible impairment whenever events or changes in business conditions warrant such a review. The carrying value of a long-lived asset is considered impaired when the anticipated separately identifiable undiscounted cash flows over the remaining useful life of the asset are less than the carrying value of the asset. In such an event, fair value is determined using discounted cash flows and if lower than the carrying value, impairment is recognized through a charge to operations.
Reclassifications	'
	Reclassifications
	Certain amounts in the fiscal 2013 and 2012 financial statements have been reclassified to conform to the fiscal 2014 presentation.
Stock Options	'
	Stock Options
	At May 31, 2014, the Company had stock option plans which are described more fully in Note 5.
	The weighted-average fair value per share of stock options granted during fiscal years 2014, 2013 and 2012, estimated on the date of grant using the Black-Scholes option pricing model, was $9.87, $9.21 and $6.94, respectively. The fair value of stock options granted was estimated using the following weighted-average assumptions:
		Year ended May 31
		2014			2013			2012
	Risk-free interest rate		0.80%			1.20%			1.20%
	Expected dividend yield		0%			0%			0%
	Expected stock price volatility		33.10%			39.20%			36.40%
	Expected option life		4.0 years			4.0 years			4.0 years
	The risk-free interest rate for periods within the expected life of options granted is based on the United States Treasury yield curve in effect at the time of grant. Expected stock price volatility is based on historical volatility of the Company’s stock. The expected option life, representing the period of time that options granted are expected to be outstanding, is based on historical option exercise and employee termination data. The Company recognizes the fair value of stock options using the accelerated method over their requisite service periods which the Company has determined to be the vesting periods.
Revenue Recognition	'
	Revenue Recognition
	Revenue from products and services is recognized when the product has been shipped or the service has been performed, the sales price is fixed and determinable, and collection of any resulting receivable is probable. To the extent customer payment is received before all recognition criteria has been met, these revenues are initially deferred and later recognized in the period that all recognition criteria has been met. Where right of return exists, allowances are made at the time of sale to reflect expected returns based on historical experience.
Shipping and Handling Costs	'
	Shipping and Handling Costs
	Shipping and handling costs that are charged to and reimbursed by the customer are recognized as revenues, while the related expenses incurred by the Company are recorded in sales and marketing expense; these expenses totaled $7,472,000, $6,856,000 and $5,940,000 in fiscal years 2014, 2013 and 2012, respectively.
Income Taxes	'
	Income Taxes
	The Company accounts for income taxes using the asset and liability method. Under this method, deferred income tax assets and liabilities are determined based on differences between the financial reporting and tax bases of assets and liabilities and for tax credit carry forwards and are measured using the enacted tax rates in effect for the years in which the differences are expected to reverse. Deferred income tax expense represents the change in net deferred income tax assets and liabilities during the year.
	The Company’s foreign subsidiaries are comprised of Neogen Europe (wholly-owned subsidiary), Neogen Latinoamerica (90% owned subsidiary), Neogen do Brasil (90% owned subsidiary) and Neogen China (wholly-owned subsidiary). Based on historical experience, as well as the Company’s future plans, earnings from these subsidiaries are expected to be re-invested indefinitely for future expansion and working capital needs. Furthermore, the Company’s domestic operations have historically produced sufficient operating cash flow to mitigate the need to remit foreign earnings. On an annual basis, the Company evaluates the current business environment and whether any new events or other external changes might require a re-evaluation of the decision to indefinitely re-invest foreign earnings. At May 31, 2014, unremitted earnings of the foreign subsidiaries were $18,262,000.
Research and Development Costs	'
	Research and Development Costs
	Research and development costs are expensed as incurred.
Advertising Costs	'
	Advertising Costs
	Advertising costs are expensed as incurred and totaled $1,344,000, $1,055,000 and $1,001,000 in fiscal years 2014, 2013 and 2012, respectively.
Net Income Attributable to Neogen per Share	'
	Net Income Attributable to Neogen per Share
	Basic net income per share is based on the weighted average number of common shares outstanding during each year. Diluted earnings per share is based on the weighted average number of common shares and dilutive potential common shares outstanding. The Company’s dilutive potential common shares outstanding during the years result entirely from dilutive stock options. The following table presents the net income per share calculations:
		Year ended May 31
	(in thousands, except per share)	2014			2013			2012
	Numerator for basic and diluted net income per share - Net income attributable to Neogen	$	28,158		$	27,190		$	22,513
	Denominator - Denominator for basic net income per share weighted average shares		36,511			35,768			35,199
	Effect of dilutive stock options		756			723			830
	Denominator for diluted net income per share		37,267			36,491			36,029
	Net income attributable to Neogen per share
	Basic	$	0.77		$	0.76		$	0.64
	Diluted	$	0.76		$	0.75		$	0.62
	At May 31, 2014, 2013 and 2012, 48,716, 88,912 and 78,450 shares, respectively, were excluded from the computations of diluted net income per share, as the option exercise prices exceeded the average market price of the common shares.
	On October 30, 2013, the Company paid a 3-for-2 stock split effected in the form of a dividend of its common stock. All share and per share amounts, with the exception of par value per share, have been adjusted to reflect the stock split as if it had taken place at the beginning of the period presented. The common stock and additional paid-in-capital accounts at May 31, 2013 and 2012 reflect the retroactive capitalization of the 3-for-2 stock split.
New Accounting Pronouncements	'
	New Accounting Pronouncements
	In February 2013, the Financial Accounting Standards Board (FASB) further amended ASC 220, Comprehensive Income, with ASU 2013-02, Comprehensive Income (Topic 220) – Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income (amended ASC 220), which was designed to improve the reporting of reclassifications out of accumulated other comprehensive income by requiring an entity to present the effect of significant reclassifications out of accumulated other comprehensive income on the respective lines of net income. The impact of adopting amended ASC 220 did not have a material impact on the consolidated financial statements.
	In May 2014, the FASB issued a new standard on revenue recognition. The new standard outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. The core principle of the revenue model is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard is designed to create greater comparability for financial statement users across industries and jurisdictions and also requires enhanced disclosures. The guidance is effective for fiscal years, and interim periods within those years, beginning after December 15, 2016. Early adoption is not permitted. The Company is currently evaluating the impact of the adoption of this standard on its consolidated financial statements.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	31-May-14
Allowance for Doubtful Accounts	'
	The activity in the allowance for doubtful accounts was as follows:
		Year ended May 31
	(In Thousands)	2014			2013			2012
	Beginning Balance	$	900		$	800		$	800
	Provision		367			193			91
	Recoveries		8			24			12
	Write-offs		(75	)		(117	)		(103	)
	Ending Balance	$	1,200		$	900		$	800
Inventories	'
	The components of inventories were as follows:
		May 31
	(In thousands)	2014			2013
	Raw materials	$	21,515		$	16,587
	Work-in-process		3,681			3,583
	Finished and purchased finished goods		25,982			18,145
		$	51,178		$	38,315
Fair Value of Stock Options Granted, Estimated using Weighted-Average Assumptions	'
	The fair value of stock options granted was estimated using the following weighted-average assumptions:
		Year ended May 31
		2014			2013			2012
	Risk-free interest rate		0.80%			1.20%			1.20%
	Expected dividend yield		0%			0%			0%
	Expected stock price volatility		33.10%			39.20%			36.40%
	Expected option life		4.0 years			4.0 years			4.0 years
Calculation of Net Income Per Share	'
	The following table presents the net income per share calculations:
		Year ended May 31
	(in thousands, except per share)	2014			2013			2012
	Numerator for basic and diluted net income per share - Net income attributable to Neogen	$	28,158		$	27,190		$	22,513
	Denominator - Denominator for basic net income per share weighted average shares		36,511			35,768			35,199
	Effect of dilutive stock options		756			723			830
	Denominator for diluted net income per share		37,267			36,491			36,029
	Net income attributable to Neogen per share
	Basic	$	0.77		$	0.76		$	0.64
	Diluted	$	0.76		$	0.75		$	0.62

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	31-May-14
Goodwill by Business Segment	'
	The following table summarizes goodwill by reportable segment:
	(In thousands)	Food Safety		Animal Safety		Total
	Balance, May 31, 2012	$	16,696	$	36,356	$	53,052
	Goodwill acquired		0		6,439		6,439
	Balance, May 31, 2013	$	16,696	$	42,795	$	59,491
	Goodwill acquired		0		8,699		8,699
	Balance, May 31, 2014	$	16,696	$	51,494	$	68,190
Amortizable of Intangible Assets	'
	Amortizable intangible assets consisted of the following and are included in customer based intangible and other noncurrent assets within the consolidated balance sheets:
	(In thousands)	Gross		Less		Net
		Carrying		Accumulated		Carrying
		Amount		Amortization		Amount
	Licenses	$	6,701	$	1,873	$	4,828
	Covenants not to compete		474		256		218
	Patents		5,990		2,746		3,244
	Customer relationship intangibles		37,145		11,915		25,230
	Other product and service related intangibles		3,833		619		3,214
	Balance, May 31, 2014	$	54,143	$	17,409	$	36,734
	Licenses	$	4,165	$	1,409	$	2,756
	Covenants not to compete		334		186		148
	Patents		5,184		2,363		2,821
	Customer relationship intangibles		21,791		9,446		12,345
	Other product and service-related intangibles		3,809		264		3,545
	Balance, May 31, 2013	$	35,283	$	13,668	$	21,615

Equity_Compensation_Plans_Tabl

Equity Compensation Plans (Tables)	12 Months Ended
	31-May-14
Stock Option Activity	'
	Qualified and non-qualified options to purchase shares of common stock may be granted to directors, officers and employees of the Company under the terms of the Company’s stock option plans. These options are granted at an exercise price of not less than the fair market value of the stock on the date of grant. Remaining shares available for grant under stock option plans were 805,000, 1,227,000 and 1,662,000 at May 31, 2014, 2013 and 2012, respectively. Options vest ratably over three and five year periods and the contractual terms are generally five or ten years.
	(Share in thousands)	Shares			Weighted-Average		Weighted-Average
					Exercise Price		Grant Date Fair  Value
	Outstanding at May 31, 2011 (764 exercisable)		2,361		$	11.85	$	3.81
	Granted		474			23.06		6.94
	Exercised		(480	)		8.29		2.93
	Forfeited		(41	)		11.08		3.59
	Outstanding at May 31, 2012 (863 exercisable)		2,314			14.89		4.63
	Granted		459			28.67		9.21
	Exercised		(657	)		10.61		3.43
	Forfeited		(24	)		19.67		6.07
	Outstanding at May 31, 2013 (749 exercisable)		2,092			19.21		6
	Granted		512			36.44		9.87
	Exercised		(643	)		13.69		4.28
	Forfeited		(92	)		22.08		6.65
	Outstanding at May 31, 2014 (577 exercisable)		1,869			25.69		7.62
Summary of Stock Options Outstanding	'
	The following is a summary of stock options outstanding at May 31, 2014:
	(Options in thousands)
		Options Outstanding							Options Exercisable
	Range of Exercise price	Number			Average Remaining		Weighted-Average		Number		Weighted Average
					Contractual Life		Exercise Price				Exercise Price
					(in years)
	$  5.45 - $ 16.12		286			1.8	$	11.7		201	$	11.14
	16.13 - 22.91		288			2.5		19.32		152		19.57
	22.92 - 28.26		353			2.8		23.17		134		23.28
	28.27 - 32.37		439			4		28.67		90		28.67
	32.38 - 41.65		503			4.9		36.44		—		—
			1,869			3.4		25.69		577		18.91

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	31-May-14
Income Before Income Taxes	'
	Income before income taxes by source consists of the following amounts:
		Year ended May 31
	(In thousands)	2014			2013			2012
	U.S.	$	37,568		$	37,407		$	31,775
	Foreign		5,463			3,734			2,064
		$	43,031		$	41,141		$	33,839
Provision for Income Taxes	'
	The provision for income taxes consisted of the following:
		Year ended May 31
	(In thousands)	2014			2013			2012
	Current:
	U.S. Taxes	$	14,442		$	12,959		$	9,520
	Foreign		1,100			854			587
	Deferred		(542	)		287			1,343
		$	15,000		$	14,100		$	11,450
Reconciliation of Income Taxes Computed at U.S. Federal Statutory Tax Rate to Income Tax Expense	'
	The reconciliation of income taxes computed at the U.S. federal statutory tax rate to income tax expense is as follows:
		Year ended May 31
	(In thousands)	2014			2013			2012
	Tax at U.S. statutory rates	$	15,061		$	14,400		$	11,900
	Tax credits and other		(574	)		(980	)		(755	)
	Provisions for state income taxes, net of federal benefit		513			680			305
		$	15,000		$	14,100		$	11,450
Significant Components of Deferred Income Tax Liabilities and Assets	'
	Significant components of the Company’s deferred income tax liabilities and assets are as follows:
		May 31
	(In thousands)	2014			2013
	Deferred income tax liabilities
	Indefinite and long-lived assets	$	(13,759	)	$	(13,953	)
	Prepaids		(358	)		(333	)
			(14,117	)		(14,286	)
	Deferred income tax assets
	Inventories and accounts receivable		1,471			1,228
	Accrued liabilities and other		2,201			2,071
			3,672			3,299
	Net deferred income tax liabilities	$	(10,445	)	$	(10,987	)

Segment_Information_Tables

Segment Information (Tables)	12 Months Ended
	31-May-14
Segment Information	'
	Segment information is as follows:
	(In thousands)		Food Safety		Animal Safety		Corporate and			Total
							Eliminations (1)
	Fiscal 2014
	Product revenues to external customers		$	111,545	$	108,189	$	0		$	219,734
	Service revenues to external customers			4,745		22,926		0			27,671
	Total revenues to external customers			116,290		131,115		0			247,405
	Operating income (loss)			28,009		18,571		(3,189	)		43,391
	Depreciation and amortization			4,181		4,999		0			9,180
	Total assets			105,607		173,643		66,051			345,301
	Expenditures for long-lived assets			5,999		5,544		0			11,543
	Fiscal 2013
	Product revenues to external customers		$	102,971	$	81,163	$	0		$	184,134
	Service revenues to external customers			3,187		20,207		0			23,394
	Total revenues to external customers			106,158		101,370		0			207,528
	Operating income (loss)			27,366		15,858		(2,518	)		40,706
	Depreciation and amortization			3,874		3,537		0			7,411
	Total assets			93,079		121,908		75,571			290,558
	Expenditures for long-lived assets			6,046		2,851		0			8,897
	Fiscal 2012
	Product revenues to external customers		$	90,460	$	74,450	$	0		$	164,910
	Service revenues to external customers			644		18,492		0			19,136
	Total revenues to external customers			91,104		92,942		0			184,046
	Operating income (loss)			23,932		12,039		(2,232	)		33,739
	Depreciation and amortization			3,500		2,673		0			6,173
	Total assets			62,227		106,987		82,386			251,600
	Expenditures for long-lived assets			4,633		7,780		0			12,413
	-1	Includes corporate assets, including cash and cash equivalents, marketable securities, current and deferred tax accounts, and overhead expenses not allocated to specific business segments. Also includes the elimination of intersegment transactions and noncontrolling interests.

Summary_of_Quarterly_Data_Unau1

Summary of Quarterly Data (Unaudited) (Tables)	12 Months Ended
	31-May-14
Summary of Quarterly Data	'
		Quarter Ended
	(In thousands, except per share)	August		November		February		May
		2013		2013		2014		2014
	Total revenues	$	58,548	$	59,599	$	61,996	$	67,262
	Gross margin		30,364		29,491		30,705		32,038
	Net income attributable to Neogen		7,839		6,207		6,575		7,537
	Basic net income per share		0.22		0.17		0.18		0.2
	Diluted net income per share		0.21		0.17		0.18		0.2
		Quarter Ended
	(In thousands, except per share)	August		November		February		May
		2012		2012		2013		2013
	Total revenues	$	49,729	$	50,737	$	51,055	$	56,007
	Gross margin		26,494		27,306		27,313		28,381
	Net income attributable to Neogen		6,714		6,793		6,652		7,031
	Basic net income per share		0.19		0.19		0.19		0.19
	Diluted net income per share		0.19		0.18		0.19		0.19

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)

0 Months Ended

12 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

Oct. 30, 2013

31-May-14

31-May-13

31-May-12

31-May-11

31-May-14

31-May-14

31-May-14

31-May-13

31-May-12

31-May-14

31-May-13

31-May-12

31-May-14

31-May-13

31-May-12

31-May-14

31-May-13

31-May-12

31-May-14

31-May-13

31-May-14

31-May-14

31-May-14

31-May-13

Dec. 31, 2013

31-May-14

31-May-14

31-May-14

Minimum

Maximum

Buildings And Improvements

Buildings And Improvements

Buildings And Improvements

Buildings And Improvements

Buildings And Improvements

Buildings And Improvements

Furniture, Machinery and Equipment

Furniture, Machinery and Equipment

Furniture, Machinery and Equipment

Furniture, Machinery and Equipment

Furniture, Machinery and Equipment

Furniture, Machinery and Equipment

Customer Relationships

Customer Relationships

Customer Relationships

Customer Relationships

Other Intangible Assets

Other Intangible Assets

Neogen Latin America

Neogen Latin America

Neogen Do Brazil

Customer one

Minimum

Minimum

Minimum

Maximum

Maximum

Maximum

Minimum

Minimum

Minimum

Maximum

Maximum

Maximum

Minimum

Maximum

Significant Accounting Policies [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Percentage of ownership in subsidiaries

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

90.00%

90.00%

'

Percentage of ownership in subsidiaries before capital contribution

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

60.00%

'

'

'

Percentage of ownership in subsidiaries after capital contribution

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

90.00%

'

'

'

Stock Split ratio

1.5

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Account receivable percentage from major customer

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

10.00%

Cash and cash equivalents

'

$40,675,000

$50,032,000

$49,045,000

$35,844,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Short-term domestic certificates of deposit

'

17,576,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Marketable securities, maturity period

'

'

'

'

'

'91 days

'1 year

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Commercial Paper

'

18,245,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Marketable securities

'

35,821,000

35,337,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Valuation allowance for inventory

'

1,425,000

1,250,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Property, plant and equipment estimated useful life

'

'

'

'

'

'

'

'7 years

'7 years

'7 years

'39 years

'39 years

'39 years

'3 years

'3 years

'3 years

'10 years

'10 years

'10 years

'

'

'

'

'

'

'

'

'

'

Depreciation expense

'

5,383,000

4,417,000

3,646,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Finite lived intangible assets, useful life

'

'

'

'

'

'5 years

'20 years

'

'

'

'

'

'

'

'

'

'

'

'

'12 years

'12 years

'12 years

'20 years

'12 years

'12 years

'

'

'

'

Weighted-average fair value per share of stock options granted

'

$9.87

$9.21

$6.94

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shipping and handling costs

'

7,472,000

6,856,000

5,940,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unremitted earnings of foreign subsidiaries

'

18,262,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Advertising costs

'

$1,344,000

$1,055,000

$1,001,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shares excluded from computations of diluted net income per share

'

48,716

88,912

78,450

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Activity_in_Allowance_for_Doub

Activity in Allowance for Doubtful Accounts (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-12
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'
Beginning Balance	$900	$800	$800
Provision	367	193	91
Recoveries	8	24	12
Write-offs	-75	-117	-103
Ending Balance	$1,200	$900	$800

Inventories_Detail

Inventories (Detail) (USD $)	31-May-14	31-May-13
In Thousands, unless otherwise specified
Inventory [Line Items]	'	'
Raw materials	$21,515	$16,587
Work-in-process	3,681	3,583
Finished and purchased finished goods	25,982	18,145
Inventories	$51,178	$38,315

Fair_Value_of_Stock_Options_Gr

Fair Value of Stock Options Granted, Estimated using Weighted-Average Assumptions (Detail)	12 Months Ended
	31-May-14	31-May-13	31-May-12
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items]	'	'	'
Risk-free interest rate	0.80%	1.20%	1.20%
Expected dividend yield	0.00%	0.00%	0.00%
Expected stock price volatility	33.10%	39.20%	36.40%
Expected option life (in years)	'4 years	'4 years	'4 years

Calculation_of_Net_Income_Per_

Calculation of Net Income Per Share (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	31-May-14	Feb. 28, 2014	Nov. 30, 2013	Aug. 31, 2013	31-May-13	Feb. 28, 2013	Nov. 30, 2012	Aug. 31, 2012	31-May-14	31-May-13	31-May-12
Earnings Per Share [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Numerator for basic and diluted net income per share - Net income attributable to Neogen	$7,537	$6,575	$6,207	$7,839	$7,031	$6,652	$6,793	$6,714	$28,158	$27,190	$22,513
Denominator - Denominator for basic net income per share weighted average shares	'	'	'	'	'	'	'	'	36,511	35,768	35,199
Effect of dilutive stock options	'	'	'	'	'	'	'	'	756	723	830
Denominator for diluted net income per share	'	'	'	'	'	'	'	'	37,267	36,491	36,029
Net Income Attributable to Neogen Per Share	'	'	'	'	'	'	'	'	'	'	'
Basic	$0.20	$0.18	$0.17	$0.22	$0.19	$0.19	$0.19	$0.19	$0.77	$0.76	$0.64
Diluted	$0.20	$0.18	$0.17	$0.21	$0.19	$0.19	$0.18	$0.19	$0.76	$0.75	$0.62

Goodwill_By_Business_Segment_D

Goodwill By Business Segment (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13
Goodwill [Line Items]	'	'
Beginning Balance	$59,491	$53,052
Goodwill acquired	8,699	6,439
Ending Balance	68,190	59,491
Food Safety	'	'
Goodwill [Line Items]	'	'
Beginning Balance	16,696	16,696
Goodwill acquired	0	0
Ending Balance	16,696	16,696
Animal Safety	'	'
Goodwill [Line Items]	'	'
Beginning Balance	42,795	36,356
Goodwill acquired	8,699	6,439
Ending Balance	$51,494	$42,795

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Asset Table - Additional Information (Detail) (USD $)	12 Months Ended
	31-May-14	31-May-13	31-May-12
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Non-amortizable intangible assets	$9,682,000	$6,660,000	'
Amortization expense for intangible assets	3,797,000	2,994,000	2,527,000
Estimated amortization expense for period, 2015	4,158,000	'	'
Estimated amortization expense for period, 2016	3,916,000	'	'
Estimated amortization expense for period, 2017	3,770,000	'	'
Estimated amortization expense for period, 2018	3,552,000	'	'
Estimated amortization expense for period, 2019	2,955,000	'	'
Minimum	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Finite lived intangible assets, useful life	'5 years	'	'
Maximum	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Finite lived intangible assets, useful life	'20 years	'	'
Licenses	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Non-amortizable intangible assets	569,000	569,000	'
Licenses | Minimum	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Finite lived intangible assets, useful life	'5 years	'	'
Licenses | Maximum	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Finite lived intangible assets, useful life	'20 years	'	'
Trademarks	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Non-amortizable intangible assets	7,889,000	4,867,000	'
Other Intangible Assets	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Non-amortizable intangible assets	$1,224,000	$1,224,000	'
Finite lived intangible assets, useful life	'12 years	'12 years	'
Noncompete Agreements	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Finite lived intangible assets, useful life	'5 years	'	'
Patents | Minimum	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Finite lived intangible assets, useful life	'5 years	'	'
Patents | Maximum	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Finite lived intangible assets, useful life	'20 years	'	'
Customer Relationships	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Finite lived intangible assets, useful life	'12 years	'12 years	'
Customer Relationships | Minimum	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Finite lived intangible assets, useful life	'12 years	'	'
Customer Relationships | Maximum	'	'	'
Goodwill And Other Intangible Asset [Line Items]	'	'	'
Finite lived intangible assets, useful life	'20 years	'	'

Amortizable_of_Intangible_Asse

Amortizable of Intangible Assets (Detail) (USD $)	31-May-14	31-May-13
In Thousands, unless otherwise specified
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	$54,143	$35,283
Less Accumulated Amortization	17,409	13,668
Net Carrying Amount	36,734	21,615
Licenses	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	6,701	4,165
Less Accumulated Amortization	1,873	1,409
Net Carrying Amount	4,828	2,756
Noncompete Agreements	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	474	334
Less Accumulated Amortization	256	186
Net Carrying Amount	218	148
Patents	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	5,990	5,184
Less Accumulated Amortization	2,746	2,363
Net Carrying Amount	3,244	2,821
Customer Relationships	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	37,145	21,791
Less Accumulated Amortization	11,915	9,446
Net Carrying Amount	25,230	12,345
Other product and service-related intangibles	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	3,833	3,809
Less Accumulated Amortization	619	264
Net Carrying Amount	$3,214	$3,545

Business_Combinations_Addition

Business Combinations - Additional Information (Detail) (USD $)

12 Months Ended

0 Months Ended

0 Months Ended

1 Months Ended

0 Months Ended

0 Months Ended

0 Months Ended

0 Months Ended

0 Months Ended

0 Months Ended

31-May-14

31-May-14

Jul. 01, 2013

Jul. 01, 2013

Jul. 01, 2013

Oct. 01, 2012

Oct. 31, 2013

Oct. 01, 2012

Jan. 02, 2013

Jan. 02, 2013

Nov. 01, 2013

Nov. 01, 2013

Nov. 01, 2013

Nov. 01, 2013

Nov. 01, 2013

Jan. 02, 2014

Jan. 02, 2014

Jan. 02, 2014

1-May-12

31-May-13

1-May-12

Jun. 21, 2011

Jun. 21, 2011

Minimum

Maximum

SyrVet, Inc.

SyrVet, Inc.

SyrVet, Inc.

Macleod Pharmaceuticals

Macleod Pharmaceuticals

Macleod Pharmaceuticals

Scidera Genomics, LLC

Scidera Genomics, LLC

Prima Tech Incorporated

Prima Tech Incorporated

Prima Tech Incorporated

Prima Tech Incorporated

Prima Tech Incorporated

Chem Tech Ltd

Chem Tech Ltd

Chem Tech Ltd

Merial Limited.

Merial Limited.

Merial Limited.

VeroMara

VeroMara

Trademarks

Minimum

Maximum

Trademarks

Trademarks

Business Acquisition [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash consideration for purchase of business

'

'

$10,012,000

'

'

$9,918,000

'

'

$3,400,000

'

$12,068,000

'

'

'

'

$17,185,000

'

'

$3,200,000

'

'

$813,000

'

Contingent consideration potential payment

'

'

'

1,500,000

'

'

'

100,000

'

'

'

600,000

'

'

'

'

1,000,000

'

'

'

'

'

200,000

Purchase price allocation for current assets

'

'

'

'

'

'

'

'

'

35,000

'

'

'

'

'

'

'

'

'

'

110,000

'

'

Purchase price allocation for property and equipment

'

'

'

556,000

'

'

'

300,000

'

246,000

'

1,653,000

'

'

'

'

682,000

'

'

'

340,000

'

'

Allocation of purchase price for contingent consideration potential payment

'

'

'

930,000

'

'

'

100,000

'

'

'

146,000

'

'

'

'

400,000

'

'

'

600,000

'

'

Purchase price allocation for intangible assets

'

'

'

4,810,000

'

'

'

5,542,000

'

1,570,000

'

4,400,000

'

'

'

'

7,536,000

'

'

'

2,036,000

'

'

Cash paid for data

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

500,000

'

'

Reversed the remaining contingent consideration accrual to other income

'

'

'

'

'

'

38,000

'

'

'

'

'

'

'

'

'

'

'

'

100,000

'

'

'

Purchase price allocation for accounts receivable

'

'

'

747,000

'

'

'

353,000

'

'

'

963,000

'

'

'

'

380,000

'

'

'

'

'

'

Purchase price allocation for inventory

'

'

'

2,195,000

'

'

'

1,238,000

'

'

'

2,796,000

'

'

'

'

4,096,000

'

'

'

'

'

'

Purchase price allocation for current liabilities

'

'

'

226,000

'

'

'

82,000

'

'

'

1,840,000

'

'

'

'

184,000

'

'

'

'

'

'

Purchase price allocation for deferred tax liabilities, current

'

'

'

'

'

'

'

2,054,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash paid for contingent consideration

'

'

'

'

'

'

62,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Purchase price allocation for non-amortizable trademarks

'

'

'

'

790,000

'

'

'

'

'

'

'

'

'

1,500,000

'

'

662,000

'

'

'

'

'

Finite lived intangible assets, useful life

'5 years

'20 years

'15 years

'

'

'

'

'

'

'

'

'

'5 years

'15 years

'

'15 years

'

'

'

'

'

'

'

Purchase price allocation for prepaid assets

'

'

'

'

'

'

'

'

'

'

'

$8,000

'

'

'

'

$225,000

'

'

'

'

'

'

Long_Term_Debt_Additional_Info

Long Term Debt - Additional Information (Detail) (USD $)	12 Months Ended
	30-May-14
Debt Instrument [Line Items]	'
Unsecured revolving line of credit, total amount available	$12,000,000
Unsecured revolving line of credit, maturity date	1-Sep-17
Unsecured revolving line of credit, interest terms	'LIBOR plus 100 basis points
Unsecured revolving line of credit, spread	1.00%
Unsecured revolving line of credit, interest rate	1.15%
Before Amendment	'
Debt Instrument [Line Items]	'
Unsecured revolving line of credit, maturity date	1-Sep-14

Equity_Compensation_Plans_Addi

Equity Compensation Plans - Additional Information (Detail) (USD $)	12 Months Ended
	31-May-14	31-May-13	31-May-12
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Number of shares available for grant	805,000	1,227,000	1,662,000
Options Exercisable, Weighted Average Exercise Price	$18.91	$14.21	'
Aggregate intrinsic value of options outstanding	$22,751,000	$35,778,000	$25,617,000
Aggregate intrinsic value of options exercisable	10,984,000	16,557,000	12,855,000
Aggregate intrinsic value of options exercised	17,669,000	12,519,000	8,226,000
Remaining compensation cost to be expensed in future periods for non-vested options	'	$4,096,000	'
Weighted average expense recognition period	'	'3 years 2 months 12 days	'
Number of shares purchased by employees	18,466	22,388	21,216
Employee Stock Purchase Plan | 2011 Employee Stock Purchase Plan	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Number of additional shares authorized	375,000	'	'
Annual maximum limit percentage of compensation to purchase shares	5.00%	'	'
Employee stock purchase plan stock price percentage	10.00%	'	'
Employee Stock Purchase Plan | 2002 Employee Stock Purchase Plan	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Number of shares available for grant	65,309	'	'
Number of shares authorized for grant	337,500	'	'
Minimum	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Stock option vesting period	'3 years	'	'
Stock option contractual terms	'5 years	'	'
Maximum	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Stock option vesting period	'5 years	'	'
Stock option contractual terms	'10 years	'	'

Stock_Option_Activity_Detail

Stock Option Activity (Detail) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	31-May-14	31-May-13	31-May-12
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'	'	'
Shares Outstanding, Beginning Balance	2,092	2,314	2,361
Shares, Granted	512	459	474
Shares, Exercised	-643	-657	-480
Shares, Forfeited	-92	-24	-41
Shares Outstanding, Ending Balance	1,869	2,092	2,314
Weighted-Average Exercise Price, Beginning Balance	$19.21	$14.89	$11.85
Weighted-Average Exercise Price, Granted	$36.44	$28.67	$23.06
Weighted-Average Exercise Price, Exercised	$13.69	$10.61	$8.29
Weighted-Average Exercise Price, Forfeited	$22.08	$19.67	$11.08
Weighted-Average Exercise Price, Ending Balance	$25.69	$19.21	$14.89
Weighted-Average Grant Date Fair Value, Beginning Balance	$6	$4.63	$3.81
Weighted-Average Grant Date Fair Value, Granted	$9.87	$9.21	$6.94
Weighted-Average Grant Date Fair Value, Exercised	$4.28	$3.43	$2.93
Weighted-Average Grant Date Fair Value, Forfeited	$6.65	$6.07	$3.59
Weighted-Average Grant Date Fair Value, Ending Balance	$7.62	$6	$4.63

Stock_Option_Activity_Parenthe

Stock Option Activity (Parenthetical) (Detail)	31-May-14	31-May-13	31-May-12	31-May-11
In Thousands, unless otherwise specified
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'	'	'	'
Shares Outstanding, Exercisable Beginning Balance	577	749	863	764

Summary_of_Stock_Options_Outst

Summary of Stock Options Outstanding (Detail) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	31-May-14	31-May-13	31-May-12	31-May-11
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'	'	'	'
Options Outstanding, Number	1,869	2,092	2,314	2,361
Options Outstanding, Average Remaining Contractual Life	'3 years 4 months 24 days	'	'	'
Options Outstanding, Weighted-Average Exercise Price	$25.69	$19.21	$14.89	$11.85
Options Exercisable, Number	577	749	863	764
Options Exercisable, Weighted Average Exercise Price	$18.91	$14.21	'	'
$5.45 - $16.12	'	'	'	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'	'	'	'
Range of Exercise price, minimum	$5.45	'	'	'
Range of Exercise price, maximum	$16.12	'	'	'
Options Outstanding, Number	286	'	'	'
Options Outstanding, Average Remaining Contractual Life	'1 year 9 months 18 days	'	'	'
Options Outstanding, Weighted-Average Exercise Price	$11.70	'	'	'
Options Exercisable, Number	201	'	'	'
Options Exercisable, Weighted Average Exercise Price	$11.14	'	'	'
$16.13 - $22.91	'	'	'	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'	'	'	'
Range of Exercise price, minimum	$16.13	'	'	'
Range of Exercise price, maximum	$22.91	'	'	'
Options Outstanding, Number	288	'	'	'
Options Outstanding, Average Remaining Contractual Life	'2 years 6 months	'	'	'
Options Outstanding, Weighted-Average Exercise Price	$19.32	'	'	'
Options Exercisable, Number	152	'	'	'
Options Exercisable, Weighted Average Exercise Price	$19.57	'	'	'
$22.92 - $28.26	'	'	'	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'	'	'	'
Range of Exercise price, minimum	$22.92	'	'	'
Range of Exercise price, maximum	$28.26	'	'	'
Options Outstanding, Number	353	'	'	'
Options Outstanding, Average Remaining Contractual Life	'2 years 9 months 18 days	'	'	'
Options Outstanding, Weighted-Average Exercise Price	$23.17	'	'	'
Options Exercisable, Number	134	'	'	'
Options Exercisable, Weighted Average Exercise Price	$23.28	'	'	'
$28.27 - $32.37	'	'	'	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'	'	'	'
Range of Exercise price, minimum	$28.27	'	'	'
Range of Exercise price, maximum	$32.37	'	'	'
Options Outstanding, Number	439	'	'	'
Options Outstanding, Average Remaining Contractual Life	'4 years	'	'	'
Options Outstanding, Weighted-Average Exercise Price	$28.67	'	'	'
Options Exercisable, Number	90	'	'	'
Options Exercisable, Weighted Average Exercise Price	$28.67	'	'	'
$32.38 - $41.65	'	'	'	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'	'	'	'
Range of Exercise price, minimum	$32.38	'	'	'
Range of Exercise price, maximum	$41.65	'	'	'
Options Outstanding, Number	503	'	'	'
Options Outstanding, Average Remaining Contractual Life	'4 years 10 months 24 days	'	'	'
Options Outstanding, Weighted-Average Exercise Price	$36.44	'	'	'

Income_Before_Income_Taxes_Det

Income Before Income Taxes (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-12
Income Before Income Taxes [Line Items]	'	'	'
Income Before Income Taxes	$43,031	$41,141	$33,839
U.S.	'	'	'
Income Before Income Taxes [Line Items]	'	'	'
Income Before Income Taxes	37,568	37,407	31,775
Foreign	'	'	'
Income Before Income Taxes [Line Items]	'	'	'
Income Before Income Taxes	$5,463	$3,734	$2,064

Provision_for_Income_Taxes_Det

Provision for Income Taxes (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-12
Current:	'	'	'
U.S. Taxes	$14,442	$12,959	$9,520
Foreign	1,100	854	587
Deferred	-542	287	1,343
Provision for Income Taxes	$15,000	$14,100	$11,450

Reconciliation_of_Income_Taxes

Reconciliation of Income Taxes Computed at the U.S. Federal Statutory Tax Rate to Income Tax Expense (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-12
Components Of Deferred Income Tax Assets And Liabilities [Line Items]	'	'	'
Tax at U.S. statutory rates	$15,061	$14,400	$11,900
Tax credits and other	-574	-980	-755
Provisions for state income taxes, net of federal benefit	513	680	305
Provision for Income Taxes	$15,000	$14,100	$11,450

Significant_Components_of_Defe

Significant Components of Deferred Income Tax Liabilities and Assets (Detail) (USD $)	31-May-14	31-May-13
In Thousands, unless otherwise specified
Deferred income tax liabilities	'	'
Indefinite and long-lived assets	($13,759)	($13,953)
Prepaids	-358	-333
Deferred Tax Liabilities, Gross	-14,117	-14,286
Deferred income tax assets	'	'
Inventories and accounts receivable	1,471	1,228
Accrued liabilities and other	2,201	2,071
Deferred Tax Assets, Net of Valuation Allowance, Total	3,672	3,299
Net deferred income tax liabilities	($10,445)	($10,987)

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	31-May-14	31-May-13	31-May-12
Income Taxes [Line Items]	'	'	'
Uncertain tax positions, reserves	'	'	$550,000
Uncertain tax position, tax rate	'	'	33.70%
Effective tax rate	34.90%	34.30%	35.50%

Commitments_and_Contingencies_

Commitments and Contingencies - Additional Information (Detail) (USD $)	12 Months Ended
	31-May-14	31-May-13	31-May-12
Commitments and Contingencies Disclosure [Line Items]	'	'	'
Environmental remediation expense, period of remediation, years	'5 years	'	'
Estimated liability costs of remediation	$916,000	$916,000	'
Estimated liability costs of remediation, current	50,000	50,000	'
Estimated liability, measurement period, years	'15 years	'	'
Royalty Expense	2,278,000	1,837,000	1,371,000
Guaranteed minimum royalty payment for period, 2015	658,000	'	'
Guaranteed minimum royalty payment for period, 2016	700,000	'	'
Guaranteed minimum royalty payment for period, 2017	669,000	'	'
Guaranteed minimum royalty payment for period, 2018	769,000	'	'
Office and Manufacturing facilities operating lease expense	856,000	657,000	495,000
Future minimum rental payments for 2015	470,000	'	'
Future minimum rental payments for 2016	324,000	'	'
Future minimum rental payments for 2017	130,000	'	'
Future minimum rental payments for 2018	74,000	'	'
Future minimum rental payments for 2019 and later	96,000	'	'
Minimum	'	'	'
Commitments and Contingencies Disclosure [Line Items]	'	'	'
Environmental remediation expense	47,000	'	'
Maximum	'	'	'
Commitments and Contingencies Disclosure [Line Items]	'	'	'
Environmental remediation expense	$79,000	'	'

Defined_Contribution_Benefit_P1

Defined Contribution Benefit Plan - Additional Information (Detail) (USD $)	12 Months Ended
	31-May-14	31-May-13	31-May-12
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Defined contribution 401(K) benefit expense	$954,000	$863,000	$760,000
First 3% employees deferred amount	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Defined contribution plan employer matching contribution	100.00%	'	'
Next 2% employees deferred amount	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Defined contribution plan employer matching contribution	50.00%	'	'

Segment_Information_Additional

Segment Information - Additional Information (Detail) (USD $)	3 Months Ended								12 Months Ended
	31-May-14	Feb. 28, 2014	Nov. 30, 2013	Aug. 31, 2013	31-May-13	Feb. 28, 2013	Nov. 30, 2012	Aug. 31, 2012	31-May-14	31-May-13	31-May-12
									Segment
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Number of reportable segments	'	'	'	'	'	'	'	'	2	'	'
Net Sales	$67,262,000	$61,996,000	$59,599,000	$58,548,000	$56,007,000	$51,055,000	$50,737,000	$49,729,000	$247,405,000	$207,528,000	$184,046,000
Foreign Operations	'	'	'	'	'	'	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net Sales	'	'	'	'	'	'	'	'	$96,111,000	$83,171,000	$76,672,000
Net Sales, percentage	'	'	'	'	'	'	'	'	38.80%	40.10%	41.70%
United States	'	'	'	'	'	'	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Long lived assets percentage	95.00%	'	'	'	95.00%	'	'	'	95.00%	95.00%	'

Segment_Information_Detail

Segment Information (Detail) (USD $)

3 Months Ended

12 Months Ended

31-May-14

Feb. 28, 2014

Nov. 30, 2013

Aug. 31, 2013

31-May-13

Feb. 28, 2013

Nov. 30, 2012

Aug. 31, 2012

31-May-14

31-May-13

31-May-12

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Product revenues to external customers

'

'

'

'

'

'

'

'

$219,734,000

$184,134,000

$164,910,000

Service revenues to external customers

'

'

'

'

'

'

'

'

27,671,000

23,394,000

19,136,000

Total revenues to external customers

67,262,000

61,996,000

59,599,000

58,548,000

56,007,000

51,055,000

50,737,000

49,729,000

247,405,000

207,528,000

184,046,000

Operating income (loss)

'

'

'

'

'

'

'

'

43,391,000

40,706,000

33,739,000

Depreciation and amortization

'

'

'

'

'

'

'

'

9,180,000

7,411,000

6,173,000

Total assets

345,301,000

'

'

'

290,558,000

'

'

'

345,301,000

290,558,000

251,600,000

Expenditures for long-lived assets

'

'

'

'

'

'

'

'

11,543,000

8,897,000

12,413,000

Operating Segments | Food Safety

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Product revenues to external customers

'

'

'

'

'

'

'

'

111,545,000

102,971,000

90,460,000

Service revenues to external customers

'

'

'

'

'

'

'

'

4,745,000

3,187,000

644,000

Total revenues to external customers

'

'

'

'

'

'

'

'

116,290,000

106,158,000

91,104,000

Operating income (loss)

'

'

'

'

'

'

'

'

28,009,000

27,366,000

23,932,000

Depreciation and amortization

'

'

'

'

'

'

'

'

4,181,000

3,874,000

3,500,000

Total assets

105,607,000

'

'

'

93,079,000

'

'

'

105,607,000

93,079,000

62,227,000

Expenditures for long-lived assets

'

'

'

'

'

'

'

'

5,999,000

6,046,000

4,633,000

Operating Segments | Animal Safety

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Product revenues to external customers

'

'

'

'

'

'

'

'

108,189,000

81,163,000

74,450,000

Service revenues to external customers

'

'

'

'

'

'

'

'

22,926,000

20,207,000

18,492,000

Total revenues to external customers

'

'

'

'

'

'

'

'

131,115,000

101,370,000

92,942,000

Operating income (loss)

'

'

'

'

'

'

'

'

18,571,000

15,858,000

12,039,000

Depreciation and amortization

'

'

'

'

'

'

'

'

4,999,000

3,537,000

2,673,000

Total assets

173,643,000

'

'

'

121,908,000

'

'

'

173,643,000

121,908,000

106,987,000

Expenditures for long-lived assets

'

'

'

'

'

'

'

'

5,544,000

2,851,000

7,780,000

Corporate Eliminations

'

'

'

'

'

'

'

'

'

'

'

Segment Reporting Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Product revenues to external customers

'

'

'

'

'

'

'

'

0

[1]

0

[1]

0

[1]

Service revenues to external customers

'

'

'

'

'

'

'

'

0

[1]

0

[1]

0

[1]

Total revenues to external customers

'

'

'

'

'

'

'

'

0

[1]

0

[1]

0

[1]

Operating income (loss)

'

'

'

'

'

'

'

'

-3,189,000

[1]

-2,518,000

[1]

-2,232,000

[1]

Depreciation and amortization

'

'

'

'

'

'

'

'

0

[1]

0

[1]

0

[1]

Total assets

66,051,000

[1]

'

'

'

75,571,000

[1]

'

'

'

66,051,000

[1]

75,571,000

[1]

82,386,000

[1]

Expenditures for long-lived assets

'

'

'

'

'

'

'

'

$0

[1]

$0

[1]

$0

[1]

[1]

Includes corporate assets, including cash and cash equivalents, marketable securities, current and deferred tax accounts, and overhead expenses not allocated to specific business segments. Also includes the elimination of intersegment transactions and noncontrolling interests.

Stock_Repurchase_Additional_In

Stock Repurchase - Additional Information (Detail) (USD $)	12 Months Ended
	31-May-14	Dec. 31, 2008
Stock Repurchase Program [Line Items]	'	'
Shares authorized to purchase	'	1,125,000
Cumulative number of shares repurchased	112,026	'
Cost of repurchased shares, including commissions	$923,000	'

Summary_of_Quarterly_Data_Deta

Summary of Quarterly Data (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	31-May-14	Feb. 28, 2014	Nov. 30, 2013	Aug. 31, 2013	31-May-13	Feb. 28, 2013	Nov. 30, 2012	Aug. 31, 2012	31-May-14	31-May-13	31-May-12
Quarterly Financial Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Total revenues	$67,262	$61,996	$59,599	$58,548	$56,007	$51,055	$50,737	$49,729	$247,405	$207,528	$184,046
Gross margin	32,038	30,705	29,491	30,364	28,381	27,313	27,306	26,494	122,598	109,494	92,425
Net income attributable to Neogen	$7,537	$6,575	$6,207	$7,839	$7,031	$6,652	$6,793	$6,714	$28,158	$27,190	$22,513
Basic net income per share	$0.20	$0.18	$0.17	$0.22	$0.19	$0.19	$0.19	$0.19	$0.77	$0.76	$0.64
Diluted net income per share	$0.20	$0.18	$0.17	$0.21	$0.19	$0.19	$0.18	$0.19	$0.76	$0.75	$0.62