Penford (PENX) 10-Q 8 Jul 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	31-May-14	Jul. 02, 2014
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	31-May-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q3	'
Trading Symbol	'PENX	'
Entity Registrant Name	'PENFORD CORP	'
Entity Central Index Key	'0000739608	'
Current Fiscal Year End Date	'--08-31	'
Entity Filer Category	'Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	12,705,538

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $)	31-May-14	Aug. 31, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$383	$221
Trade accounts receivable, net	45,320	43,432
Inventories	38,298	33,992
Prepaid expenses	4,297	3,100
Material and supplies	5,441	4,634
Other current assets	6,206	4,735
Total current assets	99,945	90,114
Property, plant and equipment, net	111,761	112,141
Restricted cash value of life insurance	7,815	7,837
Deferred tax assets	'	4,987
Other assets	1,013	1,248
Other intangible assets, net	6,182	313
Goodwill, net	9,912	7,978
Total assets	236,628	224,618
Current liabilities:	'	'
Cash overdraft, net	6,088	5,072
Current portion of long-term debt and capital lease obligations	178	231
Accounts payable	22,554	20,656
Short-term financing arrangements	1,992	1,474
Accrued liabilities	9,073	8,207
Total current liabilities	39,885	35,640
Long-term debt and capital lease obligations	77,163	72,739
Other postretirement benefits	16,754	16,596
Pension benefit liability	5,224	10,552
Other liabilities	6,103	6,198
Total liabilities	145,129	141,725
Commitments and contingencies (Note 12)	'	'
Shareholders' equity:	'	'
Common stock, par value $1.00 per share, authorized 29,000 shares, issued 14,687 and 14,479 shares, respectively, including treasury shares	14,513	14,454
Preferred stock, par value $1.00 per share, authorized 1,000 shares, none issued	'	'
Additional paid-in capital	106,054	105,166
Retained earnings	8,447	3,649
Treasury stock, at cost, 1,981 shares	-32,757	-32,757
Accumulated other comprehensive loss	-4,758	-7,619
Total shareholders' equity	91,499	82,893
Total liabilities and shareholders' equity	$236,628	$224,618

CONDENSED_CONSOLIDATED_BALANCE1

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) (USD $)	31-May-14	Aug. 31, 2013
In Thousands, except Per Share data, unless otherwise specified
Statement Of Financial Position [Abstract]	'	'
Common stock, par value	$1	$1
Common stock, shares authorized	29,000	29,000
Common stock, shares issued	14,687	14,479
Preferred stock, par value	$1	$1
Preferred stock, share authorized	1,000	1,000
Preferred stock, share issued	0	0
Treasury stock, shares	1,981	1,981

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	31-May-14	31-May-13	31-May-14	31-May-13
Income Statement [Abstract]	'	'	'	'
Sales	$119,429	$121,719	$334,786	$349,823
Cost of sales	104,561	108,528	297,041	312,373
Gross margin	14,868	13,191	37,745	37,450
Operating expenses	8,668	7,326	24,319	22,269
Research and development expenses	1,275	1,590	3,950	4,356
Income from operations	4,925	4,275	9,476	10,825
Interest expense	-935	-998	-2,564	-3,062
Other non-operating income, net	1,014	146	1,028	68
Income before income taxes	5,004	3,423	7,940	7,831
Income tax expense	1,933	1,365	3,142	2,875
Net income	$3,071	$2,058	$4,798	$4,956
Weighted-average common shares and equivalents outstanding:	'	'	'	'
Basic	12,532	12,395	12,502	12,349
Diluted	12,875	12,670	12,847	12,548
Earnings per common share:	'	'	'	'
Basic earnings per share	$0.24	$0.17	$0.38	$0.40
Diluted earnings per share	$0.24	$0.16	$0.37	$0.39

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-14	31-May-13
Statement Of Income And Comprehensive Income [Abstract]	'	'	'	'
Net income	$3,071	$2,058	$4,798	$4,956
Other comprehensive income (loss), net of tax:	'	'	'	'
Change in fair value of derivatives, net of tax benefit (expense) of $1,324; $10; $3,695; and $(147), respectively	-2,044	-17	-5,912	239
(Gain) loss from derivative transactions reclassified into earnings, net of tax (expense) benefit of $1,542; $(92); $3,642; and $(1,526), respectively	2,474	-149	5,842	-2,490
Change in postretirement liabilities, net of tax expense of $1,616; $0; $1,616; and $0	2,705	'	2,705	'
Amortization of prior service cost, net of taxes of $8, $8, $24, and $25, respectively	12	13	36	41
Amortization of actuarial loss, net of taxes of $17, $209, $117, and $627, respectively	28	341	190	1,023
Other comprehensive income (loss)	3,175	188	2,861	-1,187
Total comprehensive income	$6,246	$2,246	$7,659	$3,769

CONDENSED_CONSOLIDATED_STATEME2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) (Parenthetical) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-14	31-May-13
Statement Of Income And Comprehensive Income [Abstract]	'	'	'	'
Change in fair value of derivatives, Tax benefit (expense)	$1,324	$10	$3,695	($147)
(Gain) loss from derivative transactions reclassified into earnings, Tax (expense) benefit	1,542	-92	3,642	-1,526
Change in postretirement liabilities, Taxes	1,616	0	1,616	0
Amortization of prior service cost, Taxes	8	8	24	25
Amortization of actuarial loss, Taxes	$17	$209	$117	$627

CONDENSED_CONSOLIDATED_STATEME3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13
Cash flows from operating activities:	'	'
Net income	$4,798	$4,956
Adjustments to reconcile net income to net cash provided by operations:	'	'
Depreciation and amortization	9,674	10,128
Stock-based compensation	841	1,102
Deferred income tax expense	3,117	2,845
Non-cash loss on hedging transactions	493	1,913
Non-cash loan forgiveness (Note 4)	-1,000	'
Excess tax benefit from stock-based compensation	-152	-46
Other	-1	12
Change in assets and liabilities:	'	'
Trade accounts receivable	-653	-2,591
Inventories	-2,680	-2,910
Prepaid expenses	-1,149	-1,443
Material and supplies	-807	-481
Other current assets	-1,471	2,215
Increase in margin accounts	-354	-3,009
Accounts payable and accrued liabilities	727	-855
Pension and other postretirement benefit contributions	-2,382	-964
Pension and other postretirement benefit costs	1,899	3,830
Other	437	-122
Net cash flow provided by operating activities	11,337	14,580
Cash flows from investing activities:	'	'
Acquisitions of property, plant and equipment, net	-8,073	-8,308
Acquisitions of Gum Technology, net	-9,086	'
Settlement of ethanol construction claim	'	2,106
Other	-257	1
Net cash used in investing activities	-17,416	-6,201
Cash flows from financing activities:	'	'
Proceeds from revolving line of credit	24,100	18,200
Payments on revolving line of credit	-19,156	-23,800
Payments of long-term debt	-367	-150
Payments under capital lease obligations	-118	-209
Proceeds from financing arrangements	1,992	2,019
Payments on financing arrangements	-1,474	-893
Excess tax benefit from stock-based compensation	152	46
Exercise of stock options	106	293
Increase (decrease) in cash overdraft	1,016	-3,781
Other	-10	-1
Net cash provided by (used in) financing activities	6,241	-8,276
Increase in cash and cash equivalents	162	103
Cash and cash equivalents, beginning of period	221	154
Cash and cash equivalents, end of period	$383	$257

Business

Business	9 Months Ended
	31-May-14
Accounting Policies [Abstract]	'
Business	'
	1—BUSINESS
	Penford Corporation (which, together with its subsidiary companies, is referred to herein as “Penford” or the “Company”) is a developer, manufacturer and marketer of specialty natural-based ingredient systems for food and industrial applications, including fuel grade ethanol. Penford’s products provide convenient and cost-effective solutions derived from renewable sources. Sales of the Company’s products are generated using a combination of direct sales and distributor agreements.
	The Company has significant research and development capabilities, which are used in applying the complex chemistry of carbohydrate-based materials and in developing applications to address customer needs. In addition, the Company has specialty processing capabilities for a variety of modified starches.
	Penford manages its business in two segments: Industrial Ingredients and Food Ingredients. These segments are based on broad categories of end-market users. The Industrial Ingredients segment is a supplier of specialty starches to the paper, packaging and other industries, and is a producer of fuel grade ethanol. The Industrial Ingredients segment also sells the by-products from its corn wet milling manufacturing operations, primarily germ, fiber and gluten to customers who use these by-products as animal feed or to produce corn oil. The Food Ingredients segment is a developer and manufacturer of specialty starches and dextrins for the food manufacturing and food service industries. See Note 10 for financial information regarding the Company’s business segments.
	In March 2014, the Company completed the acquisition of Gum Technology, an Arizona close corporation (“Gum Technology”), for a purchase price of $9.9 million, subject to certain adjustments. Gum Technology blends and distributes gums and hydrocolloids and customizes stabilizers to meet customers’ product formulation needs. The acquisition of this business will broaden the Company’s food ingredients portfolio of functional and specialty ingredient systems within its Food Ingredients segment. See Note 13.

Basis_of_Presentation

Basis of Presentation	9 Months Ended
	31-May-14
Accounting Policies [Abstract]	'
Basis of Presentation	'
	2—BASIS OF PRESENTATION
	Consolidation
	The accompanying condensed consolidated financial statements include the accounts of Penford and its wholly owned subsidiaries. All intercompany transactions and balances have been eliminated. The condensed consolidated balance sheet at May 31, 2014 and the condensed consolidated statements of operations, comprehensive income (loss) and cash flows for the interim periods ended May 31, 2014 and 2013 have been prepared by the Company without audit. In the opinion of management, all adjustments, consisting only of normal recurring adjustments, which are necessary to present fairly the financial information, have been made. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). The results of operations for interim periods are not necessarily indicative of the operating results of a full year or of future operations. Certain reclassifications have been made to prior year’s financial statements in order to conform to the current year presentation. The accompanying condensed consolidated financial statements should be read in conjunction with the consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended August 31, 2013.
	Use of Estimates
	The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Estimates are used in accounting for, among other things, the allowance for doubtful accounts; the determination of potential write downs for lower-of-cost-or-market inventory evaluations; the reserve for obsolete inventory; accruals; legal contingencies; the determination of fair value of net assets acquired in a business combination; the determination of assumptions for pension and postretirement employee benefit costs; useful lives of property, plant and equipment; the assessment of a potential impairment of goodwill or long-lived assets and income taxes, including the determination of a need for a valuation allowance for deferred tax assets. Actual results may differ from previously estimated amounts.
	Change in Estimate
	During the third quarter of fiscal year 2014, the Company changed its estimates for useful lives of certain machinery and equipment used by the Industrial Ingredients segment to better match depreciation expense of these assets with the periods in which these assets are expected to generate revenue. The new estimated useful lives were established based on manufacturing engineering data and external benchmark data and were generally increased as compared to the previous estimates. The Company accounted for this as a prospective change in accounting estimate as of May 1, 2014, thereby impacting the current quarter and future periods. The change in the estimate lowered depreciation expense as compared to the amount that would have been recorded using the historical estimated useful lives. The effect of this change on net income for the quarter ended May 31, 2014 was $136,000 and the effect on diluted earnings per share for the quarter was an increase of $0.01 per share.
	Accounting Pronouncements Adopted
	In February 2013, the Financial Accounting Standards Board (“FASB”) issued guidance requiring entities to provide information about the amounts reclassified out of Accumulated other comprehensive income by component. Entities are required to present, either on the face of the financial statements or in the notes, significant amounts reclassified out of Accumulated other comprehensive income by the respective line items of net income. This guidance did not change the current requirements for reporting net income or other comprehensive income. The Company adopted this guidance effective September 1, 2013, and the required disclosure is presented in Note 6.
	In December 2011, the FASB issued guidance creating new disclosure requirements about the nature of an entity’s rights of setoff and related arrangements associated with its financial instruments and derivative instruments. The Company adopted this guidance effective September 1, 2013, and the required disclosure is presented in Note 9.
	In July 2013, the FASB issued guidance designed to reduce diversity in practice of financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss or a tax credit carryforward exists. The Company adopted this accounting presentation effective September 1, 2013. The Company complied with the prescribed accounting presentation in prior periods; therefore, the adoption of this guidance had no impact on the presentation of the Company’s financial statements.
	Recent Accounting Pronouncements
	On May 28, 2014, the FASB issued guidance that requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The guidance will replace most existing revenue recognition guidance when it becomes effective. The new standard is effective for the Company on September 1, 2017, and early application is not permitted. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is evaluating the effect that this new guidance will have on its consolidated financial statements and related disclosures. The Company has not selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting.

Balance_Sheet_Details

Balance Sheet Details	9 Months Ended
	31-May-14
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'
Balance Sheet Details	'
	3—BALANCE SHEET DETAILS
	The components of inventory were as follows:
	(In thousands)	May 31,			August 31,
		2014			2013
	Raw materials	$	9,453		$	10,381
	Work in progress		1,430			1,913
	Finished goods		27,415			21,698
	Total inventories	$	38,298		$	33,992
	The components of property, plant and equipment, net were as follows:
	(In thousands)	May 31,			August 31,
		2014			2013
	Land and land improvements	$	12,159		$	11,881
	Plant and equipment		363,974			359,909
	Construction in progress		8,657			5,255
			384,790			377,045
	Accumulated depreciation		(273,029	)		(264,904	)
	Net property, plant and equipment	$	111,761		$	112,141
	At May 31, 2014 and August 31, 2013, the Company had approximately $0.7 million and $0.7 million, respectively, of payables related to property, plant and equipment that have been excluded from acquisitions of property, plant and equipment in the consolidated statements of cash flows.
	Components of accrued liabilities were as follows:
	(In thousands)	May 31,			August 31,
		2014			2013
	Employee-related costs	$	3,977		$	3,931
	Other accrued liabilities		5,096			4,276
	Total accrued liabilities	$	9,073		$	8,207
	Employee-related costs included accrued payroll, compensated absences, payroll taxes, benefits and incentives.

Debt

Debt	9 Months Ended
	31-May-14
Debt Disclosure [Abstract]	'
Debt	'
	4—DEBT
	As of May 31, 2014, the Company had $76.5 million outstanding on its $130 million secured revolving credit facility (which, as amended, is referred to herein as the “2012 Agreement”) with a syndicate of banks. The lenders’ loan commitment may be increased under certain circumstances. On March 21, 2014, in connection with the Company’s acquisition of Gum Technology, the 2012 Agreement was amended to adjust certain financial covenants.
	The maturity date for the revolving loans under the 2012 Agreement is July 9, 2017. Interest rates under the 2012 Agreement are based on either the London Interbank Offered Rate (“LIBOR”) or the prime rate, depending on the selection of available borrowing options under the 2012 Agreement. Pursuant to the 2012 Agreement, the interest rate margin over LIBOR can range between 2% and 4%, depending upon the ratio of the Company’s funded debt to earnings before interest, taxes, depreciation and amortization (defined in the 2012 Agreement as the “Total Leverage Ratio”).
	The 2012 Agreement provides that the Total Leverage Ratio shall not exceed 4.25 on May 31, 2014, 3.50 on August 31, 2014 and 3.0 at the end of each quarter thereafter. In addition, the Company must maintain a Fixed Charge Coverage Ratio, as defined in the 2012 Agreement of not less than 1.35. Annual capital expenditures will be restricted to $15 million ($17.5 million for fiscal 2014) if the Total Leverage Ratio is greater than 2.50 for the last two consecutive fiscal quarters. The Company’s obligations under the 2012 Agreement are secured by substantially all of the Company’s assets. At May 31, 2014, the Company was in compliance with the covenants of the 2012 Agreement.
	In 2009, the Iowa Department of Economic Development (“IDED”) provided two five-year non-interest bearing loans to the Company with terms as follows: (1) a $1.0 million term loan to be repaid in 60 equal monthly payments of $16,667 beginning December 1, 2009; and (2) a $1.0 million loan, which was forgivable if the Company maintained certain levels of employment at the Cedar Rapids plant. During the third quarter of fiscal 2014, the Company repaid the outstanding balance on the $1.0 million term loan. In May 2014, the Company was notified by IDED that its obligations to maintain certain levels of employment at the Cedar Rapids plant had been met and that repayment of the $1.0 million forgivable loan had been waived. The Company recorded the loan forgiveness of $1.0 million as non-operating income.
	Pursuant to the 2012 Agreement, the Company may declare and pay dividends on its common stock in an amount not to exceed, in any consecutive four quarters, the lesser of $10 million or 50% of Free Cash Flow, as defined in the 2012 Agreement. As of May 31, 2014, the Company was not permitted to pay dividends.

Income_Taxes

Income Taxes	9 Months Ended
	31-May-14
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	5—INCOME TAXES
	Effective Tax Rates
	The Company’s effective tax rates for the three- and nine-month periods ended May 31, 2014 were 38.6% and 39.6%, respectively. The difference between the effective tax rates and the U.S. federal statutory rate was primarily due to state income taxes.
	The Company’s effective tax rates for the three- and nine-month periods ended May 31, 2013 were 40% and 37%, respectively. The difference between the third quarter effective tax rate and the U.S. federal statutory tax rate was primarily due to a $0.3 million write off of deferred tax assets related to expired stock option awards. The difference between the effective tax rates and the U.S. federal statutory tax rate for the year-to-date period was primarily due to the adjustment noted above in the third quarter and state income taxes, partially offset by the tax benefit associated with the research and development tax credit. On January 2, 2013, the American Taxpayer Relief Act of 2012 was enacted, which retroactively reinstated, to January 1, 2012, several corporate tax provisions that had expired, including the research and development tax credit. The Company recorded $0.15 million in the second quarter of fiscal 2013 related to this tax credit for research and development activities in fiscal 2012, which reduced the effective tax rate by 2% for the nine-month period ended May 31, 2013.
	Valuation Allowance
	The tax valuation allowance at May 31, 2014 of $1.8 million was related primarily to the small ethanol producer tax credit carryforwards in the United States. Tax laws in the U.S. require that any net operating loss carryforwards be utilized before the Company can utilize the small ethanol producer tax credit carryforwards. Due to the expiration of the small ethanol producer tax credit carryforward period in 2014, the Company does not believe it has sufficient positive evidence to substantiate that the small ethanol producer tax credit carryforwards are realizable at a more-likely-than-not level of assurance.
	In the second quarter of fiscal 2014, the Company liquidated its Australian subsidiaries and received approval from the Australian tax authorities for the liquidation. As of August 31, 2013, the Company had provided a tax valuation allowance of $10.9 million against the entire Australian net deferred tax asset. During the quarter ended February 28, 2014, as a result of the liquidation, the previously recorded deferred tax asset and corresponding valuation allowance were reversed, resulting in no net effect on current or deferred income taxes.
	At May 31, 2014, the Company had $1.8 million of net U. S. deferred tax assets. Other than for the ethanol tax credit carryforwards discussed above, a valuation allowance has not been provided on the net U.S. deferred tax assets as of May 31, 2014. The determination of the need for a valuation allowance requires significant judgment and estimates. The Company evaluates the requirement for a valuation allowance each quarter. The Company believes that it is more likely than not that future operations and the reversal of existing taxable temporary differences will generate sufficient taxable income to realize its deferred tax assets, except for the small ethanol producer tax credit carryforwards, for which a valuation allowance has been provided.
	Uncertain Tax Positions
	In the nine-month period ended May 31, 2014, the amount of unrecognized tax benefits decreased by approximately $150,000 due to expiration of the applicable statutes of limitations. The total amount of unrecognized tax benefits at May 31, 2014 was $0.6 million, all of which, if recognized, would favorably impact the effective tax rate. At May 31, 2014, the Company had $0.1 million of accrued interest and penalties included in the long-term tax liability.
	Other
	The Company files tax returns in the U.S. federal jurisdiction and various U.S. state jurisdictions and is subject to examination by taxing authorities in all of those jurisdictions. From time to time, the Company’s tax returns are reviewed or audited by U.S. federal and various U.S. state taxing authorities. The Company believes that adjustments, if any, resulting from these reviews or audits would not be material, individually or in the aggregate, to the Company’s financial position, results of operations or liquidity. It is reasonably possible that the amount of unrecognized tax benefits related to certain of the Company’s tax positions will increase or decrease in the next twelve months as audits or reviews are initiated and settled. At this time, an estimate of the range of a reasonably possible change cannot be made. The Company is not subject to income tax examinations by U.S. federal or state jurisdictions for fiscal years prior to 2009.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Income (Loss) ("AOCI")	9 Months Ended
	31-May-14
Equity [Abstract]	'
Accumulated Other Comprehensive Income (Loss) ("AOCI")	'
	6—ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (“AOCI”)
	The following tables provide a summary of the changes in Accumulated other comprehensive income (loss) for the nine months ended May 31, 2014 and 2013:
	(In thousands)	Net Unrealized				Gains (Losses)				Accumulated
		Gains (Losses)				on				Other
		on Cash Flow				Postretirement				Comprehensive
		Hedging				Obligations,				Loss
		Instruments,				Net of Tax
		Net of Tax
	Balances at August 31, 2013	$	(856	)		$	(6,763	)		$	(7,619	)
	Other comprehensive income (loss) before reclassification adjustments, net of tax		(5,912	)			2,705				(3,207	)
	Amounts reclassified from Accumulated other comprehensive income (loss), net of tax		5,842				226				6,068
	Balances at May 31, 2014	$	(926	)		$	(3,832	)		$	(4,758	)
	(In thousands)	Net Unrealized				Gains (Losses)				Accumulated
		Gains (Losses)				on				Other
		on Cash Flow				Postretirement				Comprehensive
		Hedging				Obligations,				Loss
		Instruments,				Net of Tax
		Net of Tax
	Balances at August 31, 2012	$	1,638			$	(17,231	)		$	(15,593	)
	Other comprehensive income (loss) before reclassification adjustments, net of tax		239				—				239
	Amounts reclassified from Accumulated other comprehensive income (loss), net of tax		(2,490	)			1,064				(1,426	)
	Balances at May 31, 2013	$	(613	)		$	(16,167	)		$	(16,780	)
	Amounts reclassified from Accumulated other comprehensive income (loss) were as follows:
				Three Months Ended May 31, 2014
	(In thousands)	Location of Expense		Before Tax				Tax				Net of Tax
		(Income) Recognized in		Amount								Amount
		Net Earnings
	Pension and other postretirement benefit plans:
	Amortization of actuarial loss (gain)	Cost of sales		$	45			$	(17	)		$	28
	Amortization of prior service cost	Cost of sales			20				(8	)			12
	Total reclassification adjustments				65				(25	)			40
	Derivatives accounted for as hedges	Cost of sales			4,016				(1,542	)			2,474
	Total reclassifications into income			$	4,081			$	(1,567	)		$	2,514
				Nine Months Ended May 31, 2014
	(In thousands)	Location of Expense		Before Tax				Tax				Net of Tax
		(Income) Recognized in		Amount								Amount
		Net Earnings
	Pension and other postretirement benefit plans:
	Amortization of actuarial loss (gain)	Cost of sales		$	223			$	(87	)		$	136
	Amortization of actuarial loss (gain)	Operating/R&D expenses			84				(30	)			54
	Amortization of prior service cost	Cost of sales			24				(11	)			13
	Amortization of prior service cost	Operating/R&D expenses			36				(13	)			23
	Total reclassification adjustments				367				(141	)			226
	Derivatives accounted for as hedges	Cost of sales			9,484				(3,642	)			5,842
	Total reclassifications into income			$	9,851			$	(3,783	)		$	6,068

StockBased_Compensation

Stock-Based Compensation	9 Months Ended
	31-May-14
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Stock-Based Compensation	'
	7—STOCK-BASED COMPENSATION
	Stock Compensation Plans
	Penford maintains a long-term incentive plan known as the 2006 Long-Term Incentive Plan (which, as amended, is referred to herein as the “2006 Incentive Plan”) pursuant to which various stock-based awards may be granted to employees, directors and consultants. As of May 31, 2014, the aggregate number of shares of the Company’s common stock that were available to be issued as awards under the 2006 Incentive Plan was 186,542. In addition, any shares previously granted under the 1994 Stock Option Plan that are subsequently forfeited or not exercised will be available for future grants under the 2006 Incentive Plan. Non-qualified stock options and restricted stock awards granted under the 2006 Incentive Plan generally vest ratably over one to four years and expire seven years from the date of grant.
	General Option Information
	A summary of the stock option activity for the nine months ended May 31, 2014 was as follows:
		Number of			Weighted-		Weighted-		Aggregate
		Shares			Average		Average		Intrinsic Value
					Exercise Price		Remaining
							Term
							(in years)
	Outstanding balance, August 31, 2013		1,517,588		$	10.3
	Granted		71,000			13.53
	Exercised		(52,500	)		6.62
	Cancelled		(84,817	)		15.2
	Outstanding balance, May 31, 2014		1,451,271			10.3		3.41	$	4,985,200
	Options exercisable at May 31, 2014		1,104,773		$	11.11		2.84	$	3,397,600
	The aggregate intrinsic value disclosed in the table above represents the total pretax intrinsic value, based on the Company’s closing stock price of $11.98 as of May 31, 2014 that would have been received by the option holders had all option holders exercised on that date. The intrinsic value of options exercised during the first nine months of fiscal 2014 was $327,200.
	The Company granted 26,000 stock options under the 2006 Incentive Plan during the first nine months of fiscal 2014. The Company estimated the fair value of these stock options using the following weighted-average assumptions that resulted in the following weighted-average grant-date fair values:
	Expected volatility		56	%
	Expected life (years)		5
	Interest rate		1.1-2.1	%
	Weighted-average fair values	$	6.53
	On March 25, 2014, in connection with the acquisition of the net assets of Gum Technology discussed in Note 13, the Company entered into compensatory stock option agreements outside of the Company’s 2006 Incentive Plan with three key employees of Gum Technology. Pursuant to these agreements, the Company granted options to purchase an aggregate of 45,000 shares of the Company’s common stock at an exercise price equal to the closing price as of the close of business on March 25, 2014. These options have a term of seven years and, subject to certain conditions, vest ratably over three years.
	As of May 31, 2014, the Company had $0.7 million of unrecognized compensation cost related to non-vested stock option awards that is expected to be recognized over a weighted-average period of 1.3 years.
	Restricted Stock Awards
	The following table summarizes the restricted stock award activity for the nine months ended May 31, 2014 as follows:
		Number			Weighted-
		of Shares			Average
					Grant-Date
					Fair Value
	Nonvested at August 31, 2013		24,489		$	7.35
	Granted		173,060			12.64
	Vested		(24,489	)		7.35
	Cancelled		—			—
	Nonvested at May 31, 2014		173,060		$	12.64
	The grant-date fair value of each share of the Company’s restricted stock awards is equal to the fair value of Penford’s common stock at the grant date. The Company recognizes compensation cost for restricted stock ratably over the vesting period. As of May 31, 2014, the Company had $2.0 million of unrecognized compensation cost related to non-vested restricted stock awards that is expected to be recognized over a weighted-average period of 1.5 years.
	On January 1, 2014, each non-employee director received an award of 1,556 shares of restricted stock under the 2006 Incentive Plan at the closing stock price on December 31, 2013. The shares, totaling 15,560, vest one year from the grant date of the award.
	In the third quarter of fiscal 2014, certain key employees of the Company received awards of restricted stock aggregating 157,500 shares under the 2006 Incentive Plan at the closing stock price on the date of the grant. These shares vest ratably over three years.
	Compensation Expense
	The Company recognizes stock-based compensation expense utilizing the accelerated multiple option approach over the requisite service period, which equals the vesting period. The following table summarizes the total stock-based compensation cost and the effect on the Company’s Condensed Consolidated Statements of Operations:
		Three Months Ended May 31,					Nine Months Ended May 31,
	(In thousands)	2014			2013		2014		2013
	Cost of sales	$	4		$	—	$	4	$	—
	Operating expenses		320			290		835		1,102
	Research and development expenses		2			—		2		—
	Total stock-based compensation expense	$	326		$	290	$	841	$	1,102
	Income tax benefit		125			110		323		419
	Total stock-based compensation expense, net of tax	$	201		$	180	$	518	$	683

Pension_and_PostRetirement_Ben

Pension and Post-Retirement Benefit Plans	9 Months Ended
	31-May-14
Compensation And Retirement Disclosure [Abstract]	'
Pension and Post-Retirement Benefit Plans	'
	8—PENSION AND POST-RETIREMENT BENEFIT PLANS
	The components of the net periodic pension and post-retirement benefit costs were as follows:
	Defined Benefit Pension Plans	Three Months Ended May 31,						Nine Months Ended May 31,
	(In thousands)	2014			2013			2014			2013
	Service cost	$	237		$	486		$	1,113		$	1,458
	Interest cost		698			662			2,168			1,986
	Expected return on plan assets		(873	)		(717	)		(2,499	)		(2,151	)
	Amortization of prior service cost		58			60			174			180
	Amortization of actuarial losses		45			483			307			1,449
	Net periodic benefit cost	$	165		$	974		$	1,263		$	2,922
	Post-retirement Health Care Plans	Three Months Ended May 31,						Nine Months Ended May 31,
	(In thousands)	2014			2013			2014			2013
	Service cost	$	28		$	59		$	84		$	177
	Interest cost		222			215			666			645
	Amortization of prior service cost		(38	)		(38	)		(114	)		(114	)
	Amortization of actuarial losses		—			67						201
	Net periodic benefit cost	$	212		$	303		$	636		$	909
	In early 2014, the Company amended its Penford Corporation Retirement Plan, which is a defined benefit pension plan for certain salaried and other employees (the “Retirement Plan”) to cease the further accrual of participant benefits. As a result of the amendment to the Retirement Plan, the Company performed a remeasurement of the Retirement Plan’s pension benefit liability and the net periodic benefit cost. The discount rate for the remeasurement of the pension liability decreased from 5.24% as of August 31, 2013 to 4.91%. There was no change in the expected return on assets. Pension net periodic benefit cost decreased $0.4 million in the third quarter of fiscal 2014 as a result of the curtailment. There have been no changes in the expected pension contributions for fiscal 2014.
	The decrease in the pension benefit liability for the nine months ended May 31, 2014 was primarily due to contributions to the Company’s defined benefit pension plans of $1.8 million, return on plan assets of $3.4 million and the effect of the curtailment on the Retirement Plan’s benefit liability of $2.7 million, partially offset by actuarial losses of $0.9 million and net periodic benefit cost for the nine months ended May 31, 2014 of $1.3 million.

Fair_Value_Measurements_and_De

Fair Value Measurements and Derivative Instruments	9 Months Ended
	31-May-14
Derivative Instruments And Hedging Activities Disclosure [Abstract]	'
Fair Value Measurements and Derivative Instruments	'
	9—FAIR VALUE MEASUREMENTS AND DERIVATIVE INSTRUMENTS
	Fair Value Measurements
	Presented below are the fair values of the Company’s derivatives as of May 31, 2014 and August 31, 2013:
	(In thousands)
	As of May 31, 2014		Level 1			Level 2			Level 3			Total
	Current assets (Other):
	Commodity derivatives		$	(2,899	)	$	—		$	—		$	(2,899	)
	(In thousands)
	As of August 31, 2013		Level 1			Level 2			Level 3			Total
	Current assets (Other):
	Commodity derivatives		$	512		$	—		$	—		$	512
	The following table reconciles the gross fair value of assets and liabilities subject to offsetting arrangements to the net amounts recorded in the Condensed Consolidated Balance Sheets as Other current assets.
	(In thousands)		Gross Amounts			Gross			Net Amount of			Cash Collateral			Net
			of Recognized			Liabilities			Assets			on Deposit with			Fair Value as
			Assets			Offset in the			(Liabilities)			Counterparty			Recorded in
						Balance Sheets									Balance Sheets
	As of May 31, 2014
	Commodity derivatives		$	303		$	(3,202	)	$	(2,899	)	$	5,343		$	2,444
	As of August 31, 2013
	Commodity derivatives		$	997		$	(485	)	$	512		$	1,700		$	2,212
	The three levels of inputs that may be used to measure fair value are:
		•		Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the entity has the ability to access at the measurement date.
		•		Level 2 inputs are other than quoted prices included within Level 1 that are observable for assets and liabilities such as (1) quoted prices for similar assets or liabilities in active markets, (2) quoted prices for identical or similar assets or liabilities in markets that are not active, or (3) inputs that are derived principally or corroborated by observable market data by correlation or other means.
		•		Level 3 inputs are unobservable inputs to the valuation methodology for the assets or liabilities.
	Other Financial Instruments
	The carrying value of cash and cash equivalents, receivables and payables approximated fair value because of their short maturities. The Company’s bank debt reprices with changes in market interest rates and, accordingly, the carrying amount of such debt approximated fair value.
	Commodity Contracts
	For derivative instruments designated as fair value hedges, the gain or loss on the derivative instruments, as well as the offsetting gain or loss on the hedged firm commitments and/or inventory, are recognized in current earnings as a component of Cost of sales. For derivative instruments designated as cash flow hedges, the effective portion of the gain or loss on the derivative instruments is reported as a component of Other comprehensive income (loss), net of applicable income taxes, and recognized in earnings when the hedged exposure affects earnings. The Company recognizes the gain or loss on the derivative instrument as a component of Cost of sales in the period during which the finished goods produced from the hedged item are sold. If it is determined that the derivative instruments used are no longer effective at offsetting changes in the price of the hedged item, then the changes in fair value would be recognized in current earnings as a component of cost of sales.
	To reduce the price volatility of corn used in fulfilling some of its starch sales contracts, Penford uses readily marketable exchange-traded futures, as well as forward cash corn purchases. Penford also uses exchange-traded futures to hedge corn inventories, firm commitments to purchase corn and forecasted purchases of corn. The exchange-traded futures are not purchased or sold for trading or speculative purposes and are designated as hedges.
	Selling prices for ethanol fluctuate based on the availability and price of manufacturing inputs and the status of various government regulations and tax incentives. To reduce the risk of the price variability of ethanol, Penford enters into exchange-traded futures contracts to hedge exposure to ethanol price fluctuations. In the first quarter of fiscal 2014, the Company discontinued hedge accounting for certain ethanol futures contracts as they were not effective at offsetting changes in the selling prices of ethanol. The changes in the fair value of these futures contracts were recorded directly to Cost of sales. In the second quarter of fiscal 2014, the Company identified and entered into different exchange-traded ethanol swap contracts, which were designated as cash flow hedges.
	Prices for natural gas fluctuate due to anticipated changes in supply and demand and movement of prices of related or alternative fuels. To reduce the price risk caused by market fluctuations, Penford may use exchange-traded futures contracts to hedge exposure to natural gas price fluctuations. These futures contracts do not qualify for hedge accounting and the changes in fair value were recognized in current earnings as a component of Cost of sales.
	Hedged transactions are generally expected to occur within 12 months of the time the hedge is established. The deferred loss, net of tax, recorded in Accumulated other comprehensive loss at May 31, 2014 that is expected to be reclassified into income within 12 months is $0.9 million.
	As of May 31, 2014, the Company had the following outstanding futures contracts:
	Corn futures		4,775,000   Bushels
	Ethanol futures		14,700,000 Gallons
	Natural gas futures		40,000 mmbtu (millions of British thermal units)
	The following tables provide information about the fair values of the Company’s derivatives, by contract type, as of May 31, 2014 and August 31, 2013:
			Assets									Liabilities
	(In thousands)					Fair Value									Fair Value
			Balance Sheet			May 31,			Aug 31,			Balance Sheet			May 31,			Aug 31,
			Location			2014			2013			Location			2014			2013
	Derivatives designated as hedging instruments:
	Cash flow hedges:
	Corn futures			Other current assets		$	—		$	—			Other current assets		$	788		$	485
	Ethanol futures			Other current assets			—			997			Other current assets			2,414			—
	Fair value hedges:
	Corn futures			Other current assets			300			—			Other current assets			—			—
	Derivatives not designated as hedging instruments:
	Natural gas futures			Other current assets			3			—			Other current assets			—			—
						$	303		$	997					$	3,202		$	485
	The following tables provide information about the effect of derivative instruments on the financial performance of the Company for the three- and nine-month periods ended May 31, 2014 and 2013:
	(In thousands)		Amount of Gain (Loss)						Amount of Gain (Loss)						Amount of Gain (Loss)
			Recognized in OCI						Reclassified from						Recognized in Income
									AOCI into Income
			3 Months Ended May 31,						3 Months Ended May 31,						3 Months Ended May 31,
			2014			2013			2014			2013			2014			2013
	Derivatives designated as hedging instruments:
	Cash flow hedges:
	Corn futures (1)		$	760		$	530		$	1,744		$	596		$	(198	)	$	(474	)
	Ethanol futures (1)			(4,128	)		(557	)		(5,760	)		(355	)		(260	)		—
			$	(3,368	)	$	(27	)	$	(4,016	)	$	241		$	(458	)	$	(474	)
	Fair value hedges:
	Corn futures (1) (2)														$	(21	)	$	143
Derivatives not designated as hedging instruments:
Natural gas futures (1)														$	(854	)	$	294
Natural gas options (1)															—			(20	)
Soybean meal futures (1)															5			—
														$	(849	)	$	274
-1	Gains and losses reported in Cost of sales
-2	Hedged items are firm commitments and inventory
(In thousands)		Amount of Gain (Loss)						Amount of Gain (Loss)						Amount of Gain (Loss)
		Recognized in OCI						Reclassified from						Recognized in Income
								AOCI into Income
		9 Months Ended May 31,						9 Months Ended May 31,						9 Months Ended May 31,
		2014			2013			2014			2013			2014			2013
Derivatives designated as hedging instruments:
Cash flow hedges:
Corn futures (1)		$	81		$	(43	)	$	(2,116	)	$	4,087		$	(1,595	)	$	(589	)
Ethanol futures (1)			(9,688	)		429			(7,368	)		(71	)		(331	)		(11	)
		$	(9,607	)	$	386		$	(9,484	)	$	4,016		$	(1,926	)	$	(600	)
Fair value hedges:
Corn futures (1) (2)														$	75		$	127
Derivatives not designated as hedging instruments:
Natural gas futures (1)														$	(634	)	$	(16	)
Natural gas options (1)															—			(20	)
Soybean meal futures (1)															11
Ethanol futures (1)															64			—
														$	(559	)	$	(36	)
-1	Gains and losses reported in Cost of sales
-2	Hedged items are firm commitments and inventory

Segment_Reporting

Segment Reporting	9 Months Ended
	31-May-14
Segment Reporting [Abstract]	'
Segment Reporting	'
	10—SEGMENT REPORTING
	Financial information for the Company’s two segments, Industrial Ingredients and Food Ingredients, is presented below. These segments serve broad categories of end-market users. The Industrial Ingredients segment provides carbohydrate-based starches for industrial applications, primarily paper and packaging products and fuel grade ethanol. The Food Ingredients segment produces specialty starches for food applications. A third item for “corporate and other” activity has been presented to provide reconciliation to amounts reported in the condensed consolidated financial statements. Corporate and other represents the activities related to the corporate headquarters, such as public company reporting, personnel costs of the executive management team, corporate-wide professional services and consolidation entries.
		Three Months Ended May 31,						Nine Months Ended May 31,
	(In thousands)	2014			2013			2014			2013
	Sales:
	Industrial Ingredients:
	Industrial Starch	$	39,723		$	44,572		$	120,261		$	132,610
	Ethanol		27,952			28,111			72,966			69,710
	By-Products		16,437			20,501			47,312			64,710
			84,112			93,184			240,539			267,030
	Food Ingredients		35,317			28,535			94,247			82,793
		$	119,429		$	121,719		$	334,786		$	349,823
	Income (loss) from operations:
	Industrial Ingredients	$	1,957		$	565		$	(72	)	$	1,500
	Food Ingredients		6,025			6,206			18,349			17,097
	Corporate and other		(3,057	)		(2,496	)		(8,801	)		(7,772	)
		$	4,925		$	4,275		$	9,476		$	10,825
	(In thousands)	May 31,			August 31,
		2014			2013
	Total assets:
	Industrial Ingredients	$	136,020		$	133,120
	Food Ingredients		88,423			68,550
	Corporate and other		12,185			22,948
		$	236,628		$	224,618

Earnings_Per_Share

Earnings Per Share	9 Months Ended
	31-May-14
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	11—EARNINGS PER SHARE
	All outstanding unvested share-based payment awards that contain rights to non-forfeitable dividends participate in undistributed earnings with common shareholders and, therefore, are included in computing earnings per share under the two-class method. Under the two-class method, net earnings are reduced by the amount of dividends declared in the period for each class of common stock and participating security. The remaining undistributed earnings are then allocated to common stock and participating securities, based on their respective rights to receive dividends. Restricted stock awards granted to certain employees and directors under the Company’s 2006 Incentive Plan, which contain non-forfeitable rights to dividends at the same rate as common stock, are considered participating securities.
	Basic earnings per share reflect only the weighted-average common shares outstanding during the period. Diluted earnings per share reflect weighted-average common shares outstanding and the effect of any dilutive common stock equivalent shares. Diluted earnings per share is calculated by dividing net income by the average common shares outstanding plus additional common shares that would have been outstanding assuming the exercise of in-the-money stock options, using the treasury stock method. The following table presents the reconciliation of income from operations to income from operations applicable to common shares and the computation of diluted weighted-average shares outstanding:
		Three Months Ended May 31,						Nine Months Ended May 31,
	(In thousands)	2014			2013			2014			2013
	Numerator:
	Net income	$	3,071		$	2,058		$	4,798		$	4,956
	Less: Allocation to participating securities		(16	)		(4	)		(14	)		(15	)
	Net income applicable to common shares	$	3,055		$	2,054		$	4,784		$	4,941
	Denominator:
	Weighted average common shares outstanding, basic		12,532			12,395			12,502			12,349
	Dilutive stock options and awards		343			275			345			199
	Weighted average common shares outstanding, diluted		12,875			12,670			12,847			12,548
	Weighted-average stock options to purchase 613,462 and 614,125 shares of common stock for the three and nine months ended May 31, 2014, respectively, were excluded from the calculation of diluted earnings per share because they were antidilutive. Weighted-average stock options to purchase 916,463 and 967,820 shares of common stock for the three and nine months ended May 31, 2013, respectively, were excluded from the calculation of diluted earnings per share because they were antidilutive.

Legal_Proceedings_and_Continge

Legal Proceedings and Contingencies	9 Months Ended
	31-May-14
Commitments And Contingencies Disclosure [Abstract]	'
Legal Proceedings and Contingencies	'
	12—LEGAL PROCEEDINGS AND CONTINGENCIES
	The Company regularly evaluates the status of claims and legal proceedings in which it is involved in order to assess whether a loss is probable or there is a reasonable possibility that a loss may have been incurred, and to determine if accruals are appropriate. The Company expenses legal costs as such costs are incurred.
	Pet Product Patent Litigation
	As reported in the Company’s most recent Annual Report on Form 10-K, in June 2011 the Company was notified that a complaint had been filed against a customer of a Company subsidiary, Penford Products Co. (“Penford Products”), in the United States District Court for the District of New Jersey. The complaint alleged that certain pet products supplied by Penford Products to the customer infringed upon a patent owned by T.F.H. Publications, Inc. (the “Plaintiff”). The customer tendered the defense of this lawsuit to Penford Products pursuant to the terms of its supply agreement with Penford Products. Penford Products thereafter commenced a defense of the litigation on behalf of the customer. In April 2012, the Plaintiff filed an amended complaint alleging that certain additional products made by Penford Products for the same customer infringed upon two of the Plaintiff’s patents. In November 2013, the Plaintiff filed another amended complaint adding Penford Products as a defendant in the suit. The Plaintiff is seeking an injunction against infringement of its patents, as well as the recovery of certain damages.
	The court held a claim construction hearing on August 7, 2013, and rendered an opinion dated April 30, 2014. The Company believes that the court’s opinion substantially supports its position that none of the products supplied by Penford Products infringes upon the patents in the suit. The Company is currently evaluating further steps in the litigation. The Company cannot at this time determine the likelihood of any outcome or estimate any damages that might be awarded.
	NewPage Bankruptcy Preference Litigation
	As reported in the Company’s most recent Annual Report on Form 10-K, in late August and early September 2013, two of the Company’s subsidiaries, Penford Products and Carolina Starches, LLC (“Carolina Starches”), were served with separate complaints filed by Pirinate Consulting Group, LLC, as Litigation Trustee (the “Trustee”) for the NP Creditor Litigation Trust, as successor in interest to the bankruptcy estate of NewPage Corporation, an industrial starch customer of each subsidiary, in the United States Bankruptcy Court for the District of Delaware.
	The complaint filed against Penford Products seeks the recovery of alleged preferential transfers in the amount of approximately $778,000, together with other damages. An answer denying all liability in this matter has been filed. The Company believes that it has adequate defenses to this claim; however, the Company cannot at this time determine the likelihood of any outcome or estimate any damages that might be awarded.
	The Trustee also sought recovery of alleged preferential transfers of approximately $216,000, together with other damages, from Carolina Starches. In March 2014, Carolina Starches entered into a settlement agreement with the Trustee which provides, among other things, for the full and final settlement of this matter in exchange for a payment by Carolina Starches to the Trustee of $10,000.
	Management is unable to provide additional information regarding any possible loss in connection with the foregoing claims and proceedings because (i) the Company currently believes that the claims are not adequately supported, and (ii) there are significant factual and/or legal issues to be resolved. With regard to these matters, management does not believe, based on currently available information, that the eventual outcomes will have a material adverse effect on the Company’s financial condition, results of operations or liquidity, although the outcomes could be material to the Company’s operating results for any particular period, depending, in part, upon the operating results for such period.
	Other Claims and Litigation
	The Company is involved from time to time in various other claims and litigation arising in the normal course of business. In the judgment of management, which relies in part on information obtained from the Company’s outside legal counsel, the ultimate resolution of these other matters will not materially affect the consolidated financial position, results of operations or liquidity of the Company.

Acquisition

Acquisition	9 Months Ended
	31-May-14
Business Combinations [Abstract]	'
Acquisition	'
	13—ACQUISITION
	On March 4, 2014, Penford Products Co. (“Purchaser”), a wholly-owned subsidiary of the Company, entered into an Asset Purchase Agreement with Gum Technology, an Arizona close corporation, (“Gum Technology” or “Seller”), and Allen J Freed and Sheryl I. Freed, the owners of Seller. On March 25, 2014, the Company acquired substantially all of the assets of Seller and assumed certain liabilities for a purchase price of $9.9 million, subject to working capital and certain other adjustments.
	Gum Technology, based in Tucson, Arizona, distributes and blends gums and hydrocolloids, serving primarily the food and beverage industries in North America and Asia. Gum Technology specializes in developing and producing customized stabilizers to meet customers’ product formulation needs. This acquisition will broaden the Company’s food ingredients portfolio of functional and specialty ingredient systems within the Food Ingredients segment.
	The funding of the purchase price was provided by borrowings under the Company’s credit facility (the 2012 Agreement described in Note 4). In connection with the acquisition, $750,000 of the purchase price (“Holdback”), included in the $9.9 million total purchase price, has been retained by the Company as a fund to satisfy certain of the Seller’s post-closing obligations. The Holdback is payable to the Seller, net of amounts applied to satisfy the obligations of the Seller, in two installments at six and twelve months after the date of the acquisition. The Company incurred approximately $86,000 of acquisition costs, which were recorded as operating expenses in the Condensed Statements of Operations.
	At May 31, 2014, the acquisition was reflected in the condensed consolidated financial statements as follows:
	(In thousands)
	Cash paid at closing	$	9,086
	Accrued liabilities:
	Working capital adjustment		72
	Holdback		750
	Total purchase price	$	9,908
	The acquisition of the net assets of Gum Technology was accounted for as a business combination under the acquisition method. The preliminary allocation of the purchase price to the assets acquired and liabilities assumed, based on their fair values as of March 25, 2014, is presented below. As of the date of issuance of these financial statements, the Company has not completed its valuation analysis and calculations in sufficient detail necessary to finalize its estimates, which principally may impact the reported amounts of amortizable intangibles and goodwill. The final fair value determinations may be different than those reflected in the condensed consolidated financial statements at May 31, 2014.
	Goodwill represents the amount by which the purchase price exceeds the fair value of the net assets acquired and has been allocated to the Food Ingredients segment. It is estimated that all of the goodwill associated with this acquisition is deductible for tax purposes. Pro forma results of operations have not been included as the pro forma revenues and earnings were not significant to the historical periods. Sales of $2.1 million related to the acquired Gum Technology business were included in the Food Ingredients results of operations for the three and nine months ended May 31, 2014. Due to the integration of Gum Technology into the Food Ingredients segment, it is not practicable to determine the net earnings of Gum Technology included in the Condensed Consolidated Statements of Operations since the acquisition.
	(In thousands)
	Working capital	$	2,133
	Non-competition agreement		490
	Customer relationships		2,600
	Trade name portfolio		2,700
	Goodwill		1,934
	Other assets		51
	Total purchase price	$	9,908
	The Company entered into compensatory stock option agreements outside of the Company’s 2006 Incentive Plan with three key former employees of the Seller. Pursuant to these agreements, the Company granted options to purchase an aggregate of 45,000 shares of the Company’s common stock at an exercise price equal to the closing price as of the close of business on March 25, 2014. These options have a term of seven years and vest ratably over a three-year period. Stock-based compensation for these options recognized in operating income for the three months ended May 31, 2014 was not material.
	The Company entered into a five-year non-competition agreement with Gum Technology and the former owners of Gum Technology. The fair value of the agreement is being amortized on a straight-line basis over the term of the agreement. Other intangible assets identified were customer relationships, which are being amortized on a straight-line basis over 13 years, and a trade name portfolio, which is an indefinite-lived asset. The trade name portfolio for gums products is well recognized, and the Company plans to use the portfolio of names indefinitely. The fair values of these intangible assets were calculated utilizing Level 3 inputs to discounted cash flow models.

Basis_of_Presentation_Policies

Basis of Presentation (Policies)	9 Months Ended
	31-May-14
Accounting Policies [Abstract]	'
Consolidation	'
	Consolidation
	The accompanying condensed consolidated financial statements include the accounts of Penford and its wholly owned subsidiaries. All intercompany transactions and balances have been eliminated. The condensed consolidated balance sheet at May 31, 2014 and the condensed consolidated statements of operations, comprehensive income (loss) and cash flows for the interim periods ended May 31, 2014 and 2013 have been prepared by the Company without audit. In the opinion of management, all adjustments, consisting only of normal recurring adjustments, which are necessary to present fairly the financial information, have been made. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). The results of operations for interim periods are not necessarily indicative of the operating results of a full year or of future operations. Certain reclassifications have been made to prior year’s financial statements in order to conform to the current year presentation. The accompanying condensed consolidated financial statements should be read in conjunction with the consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended August 31, 2013.
Use of Estimates/Change in Estimate	'
	Use of Estimates
	The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Estimates are used in accounting for, among other things, the allowance for doubtful accounts; the determination of potential write downs for lower-of-cost-or-market inventory evaluations; the reserve for obsolete inventory; accruals; legal contingencies; the determination of fair value of net assets acquired in a business combination; the determination of assumptions for pension and postretirement employee benefit costs; useful lives of property, plant and equipment; the assessment of a potential impairment of goodwill or long-lived assets and income taxes, including the determination of a need for a valuation allowance for deferred tax assets. Actual results may differ from previously estimated amounts.
	Change in Estimate
	During the third quarter of fiscal year 2014, the Company changed its estimates for useful lives of certain machinery and equipment used by the Industrial Ingredients segment to better match depreciation expense of these assets with the periods in which these assets are expected to generate revenue. The new estimated useful lives were established based on manufacturing engineering data and external benchmark data and were generally increased as compared to the previous estimates. The Company accounted for this as a prospective change in accounting estimate as of May 1, 2014, thereby impacting the current quarter and future periods. The change in the estimate lowered depreciation expense as compared to the amount that would have been recorded using the historical estimated useful lives. The effect of this change on net income for the quarter ended May 31, 2014 was $136,000 and the effect on diluted earnings per share for the quarter was an increase of $0.01 per share.
Accounting Pronouncements Adopted/Recent Accounting Pronouncements	'
	Accounting Pronouncements Adopted
	In February 2013, the Financial Accounting Standards Board (“FASB”) issued guidance requiring entities to provide information about the amounts reclassified out of Accumulated other comprehensive income by component. Entities are required to present, either on the face of the financial statements or in the notes, significant amounts reclassified out of Accumulated other comprehensive income by the respective line items of net income. This guidance did not change the current requirements for reporting net income or other comprehensive income. The Company adopted this guidance effective September 1, 2013, and the required disclosure is presented in Note 6.
	In December 2011, the FASB issued guidance creating new disclosure requirements about the nature of an entity’s rights of setoff and related arrangements associated with its financial instruments and derivative instruments. The Company adopted this guidance effective September 1, 2013, and the required disclosure is presented in Note 9.
	In July 2013, the FASB issued guidance designed to reduce diversity in practice of financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss or a tax credit carryforward exists. The Company adopted this accounting presentation effective September 1, 2013. The Company complied with the prescribed accounting presentation in prior periods; therefore, the adoption of this guidance had no impact on the presentation of the Company’s financial statements.
	Recent Accounting Pronouncements
	On May 28, 2014, the FASB issued guidance that requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The guidance will replace most existing revenue recognition guidance when it becomes effective. The new standard is effective for the Company on September 1, 2017, and early application is not permitted. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is evaluating the effect that this new guidance will have on its consolidated financial statements and related disclosures. The Company has not selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting.

Balance_Sheet_Details_Tables

Balance Sheet Details (Tables)	9 Months Ended
	31-May-14
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'
Components of Inventory	'
	The components of inventory were as follows:
		May 31,			August 31,
	(In thousands)	2014			2013
	Raw materials	$	9,453		$	10,381
	Work in progress		1,430			1,913
	Finished goods		27,415			21,698
	Total inventories	$	38,298		$	33,992
Components of Property, Plant and Equipment	'
	The components of property, plant and equipment, net were as follows:
	(In thousands)	May 31,			August 31,
		2014			2013
	Land and land improvements	$	12,159		$	11,881
	Plant and equipment		363,974			359,909
	Construction in progress		8,657			5,255
			384,790			377,045
	Accumulated depreciation		(273,029	)		(264,904	)
	Net property, plant and equipment	$	111,761		$	112,141
Components of Accrued Liabilities	'
	Components of accrued liabilities were as follows:
	(In thousands)	May 31,			August 31,
		2014			2013
	Employee-related costs	$	3,977		$	3,931
	Other accrued liabilities		5,096			4,276
	Total accrued liabilities	$	9,073		$	8,207

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Loss) ("AOCI") (Tables)	9 Months Ended
	31-May-14
Equity [Abstract]	'
Summary of Changes in Accumulated Other Comprehensive Income (Loss)	'
	The following tables provide a summary of the changes in Accumulated other comprehensive income (loss) for the nine months ended May 31, 2014 and 2013:
	(In thousands)	Net Unrealized				Gains (Losses)				Accumulated
		Gains (Losses)				on				Other
		on Cash Flow				Postretirement				Comprehensive
		Hedging				Obligations,				Loss
		Instruments,				Net of Tax
		Net of Tax
	Balances at August 31, 2013	$	(856	)		$	(6,763	)		$	(7,619	)
	Other comprehensive income (loss) before reclassification adjustments, net of tax		(5,912	)			2,705				(3,207	)
	Amounts reclassified from Accumulated other comprehensive income (loss), net of tax		5,842				226				6,068
	Balances at May 31, 2014	$	(926	)		$	(3,832	)		$	(4,758	)
	(In thousands)	Net Unrealized				Gains (Losses)				Accumulated
		Gains (Losses)				on				Other
		on Cash Flow				Postretirement				Comprehensive
		Hedging				Obligations,				Loss
		Instruments,				Net of Tax
		Net of Tax
	Balances at August 31, 2012	$	1,638			$	(17,231	)		$	(15,593	)
	Other comprehensive income (loss) before reclassification adjustments, net of tax		239				—				239
	Amounts reclassified from Accumulated other comprehensive income (loss), net of tax		(2,490	)			1,064				(1,426	)
	Balances at May 31, 2013	$	(613	)		$	(16,167	)		$	(16,780	)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)	'
	Amounts reclassified from Accumulated other comprehensive income (loss) were as follows:
				Three Months Ended May 31, 2014
	(In thousands)	Location of Expense		Before Tax				Tax				Net of Tax
		(Income) Recognized in		Amount								Amount
		Net Earnings
	Pension and other postretirement benefit plans:
	Amortization of actuarial loss (gain)	Cost of sales		$	45			$	(17	)		$	28
	Amortization of prior service cost	Cost of sales			20				(8	)			12
	Total reclassification adjustments				65				(25	)			40
	Derivatives accounted for as hedges	Cost of sales			4,016				(1,542	)			2,474
	Total reclassifications into income			$	4,081			$	(1,567	)		$	2,514
				Nine Months Ended May 31, 2014
	(In thousands)	Location of Expense		Before Tax				Tax				Net of Tax
		(Income) Recognized in		Amount								Amount
		Net Earnings
	Pension and other postretirement benefit plans:
	Amortization of actuarial loss (gain)	Cost of sales		$	223			$	(87	)		$	136
	Amortization of actuarial loss (gain)	Operating/R&D expenses			84				(30	)			54
	Amortization of prior service cost	Cost of sales			24				(11	)			13
	Amortization of prior service cost	Operating/R&D expenses			36				(13	)			23
	Total reclassification adjustments				367				(141	)			226
	Derivatives accounted for as hedges	Cost of sales			9,484				(3,642	)			5,842
	Total reclassifications into income			$	9,851			$	(3,783	)		$	6,068

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	9 Months Ended
	31-May-14
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Schedule of Share Based Compensation Stock Options Activity	'
	A summary of the stock option activity for the nine months ended May 31, 2014 was as follows:
		Number of			Weighted-		Weighted-		Aggregate
		Shares			Average		Average		Intrinsic Value
					Exercise Price		Remaining
							Term
							(in years)
	Outstanding balance, August 31, 2013		1,517,588		$	10.3
	Granted		71,000			13.53
	Exercised		(52,500	)		6.62
	Cancelled		(84,817	)		15.2
	Outstanding balance, May 31, 2014		1,451,271			10.3		3.41	$	4,985,200
	Options exercisable at May 31, 2014		1,104,773		$	11.11		2.84	$	3,397,600
Schedule of Share Based Payment Award Stock Options Valuation Assumptions	'
	The Company estimated the fair value of these stock options using the following weighted-average assumptions that resulted in the following weighted-average grant-date fair values:
	Expected volatility	56%
	Expected life (years)	5
	Interest rate	1.1-2.1%
	Weighted-average fair values	$6.53
Schedule of Share-Based Compensation, Restricted Stock Award Activity	'
	The following table summarizes the restricted stock award activity for the nine months ended May 31, 2014 as follows:
		Number			Weighted-
		of Shares			Average
					Grant-Date
					Fair Value
	Nonvested at August 31, 2013		24,489		$	7.35
	Granted		173,060			12.64
	Vested		(24,489	)		7.35
	Cancelled		—			—
	Nonvested at May 31, 2014		173,060		$	12.64
Schedule of Employee Service Share-Based Compensation, Allocation of Recognized Period Costs	'
	The following table summarizes the total stock-based compensation cost and the effect on the Company’s Condensed Consolidated Statements of Operations:
		Three Months Ended May 31,					Nine Months Ended May 31,
	(In thousands)	2014			2013		2014		2013
	Cost of sales	$	4		$	—	$	4	$	—
	Operating expenses		320			290		835		1,102
	Research and development expenses		2			—		2		—
	Total stock-based compensation expense	$	326		$	290	$	841	$	1,102
	Income tax benefit		125			110		323		419
	Total stock-based compensation expense, net of tax	$	201		$	180	$	518	$	683

Pension_and_PostRetirement_Ben1

Pension and Post-Retirement Benefit Plans (Tables)	9 Months Ended
	31-May-14
Compensation And Retirement Disclosure [Abstract]	'
Components of Net Periodic Benefit Costs	'
	The components of the net periodic pension and post-retirement benefit costs were as follows:
	Defined Benefit Pension Plans	Three Months Ended May 31,						Nine Months Ended May 31,
	(In thousands)	2014			2013			2014			2013
	Service cost	$	237		$	486		$	1,113		$	1,458
	Interest cost		698			662			2,168			1,986
	Expected return on plan assets		(873	)		(717	)		(2,499	)		(2,151	)
	Amortization of prior service cost		58			60			174			180
	Amortization of actuarial losses		45			483			307			1,449
	Net periodic benefit cost	$	165		$	974		$	1,263		$	2,922
	Post-retirement Health Care Plans	Three Months Ended May 31,						Nine Months Ended May 31,
	(In thousands)	2014			2013			2014			2013
	Service cost	$	28		$	59		$	84		$	177
	Interest cost		222			215			666			645
	Amortization of prior service cost		(38	)		(38	)		(114	)		(114	)
	Amortization of actuarial losses		—			67						201
	Net periodic benefit cost	$	212		$	303		$	636		$	909

Fair_Value_Measurements_and_De1

Fair Value Measurements and Derivative Instruments (Tables)	9 Months Ended
	31-May-14
Derivative Instruments And Hedging Activities Disclosure [Abstract]	'
Fair Values of Company's Derivative Instruments	'
	Presented below are the fair values of the Company’s derivatives as of May 31, 2014 and August 31, 2013:
	(In thousands)
	As of May 31, 2014		Level 1			Level 2			Level 3			Total
	Current assets (Other):
	Commodity derivatives		$	(2,899	)	$	—		$	—		$	(2,899	)
	(In thousands)
	As of August 31, 2013		Level 1			Level 2			Level 3			Total
	Current assets (Other):
	Commodity derivatives		$	512		$	—		$	—		$	512
Reconciliation of Gross Fair Value of Assets and Liabilities Subject to Offsetting Arrangements	'
	The following table reconciles the gross fair value of assets and liabilities subject to offsetting arrangements to the net amounts recorded in the Condensed Consolidated Balance Sheets as Other current assets.
	(In thousands)		Gross Amounts			Gross			Net Amount of			Cash Collateral			Net
			of Recognized			Liabilities			Assets			on Deposit with			Fair Value as
			Assets			Offset in the			(Liabilities)			Counterparty			Recorded in
						Balance Sheets									Balance Sheets
	As of May 31, 2014
	Commodity derivatives		$	303		$	(3,202	)	$	(2,899	)	$	5,343		$	2,444
	As of August 31, 2013
	Commodity derivatives		$	997		$	(485	)	$	512		$	1,700		$	2,212
Outstanding Futures Contracts	'
	As of May 31, 2014, the Company had the following outstanding futures contracts:
	Corn futures			4,775,000		Bushels
	Ethanol futures			14,700,000		Gallons
	Natural gas futures			40,000		mmbtu (millions of British thermal units)
Fair Values of Company's Derivatives by Contract Type	'
	The following tables provide information about the fair values of the Company’s derivatives, by contract type, as of May 31, 2014 and August 31, 2013:
			Assets									Liabilities
	(In thousands)					Fair Value									Fair Value
			Balance Sheet			May 31,			Aug 31,			Balance Sheet			May 31,			Aug 31,
			Location			2014			2013			Location			2014			2013
	Derivatives designated as hedging instruments:
	Cash flow hedges:
	Corn futures			Other current assets		$	—		$	—			Other current assets		$	788		$	485
	Ethanol futures			Other current assets			—			997			Other current assets			2,414			—
	Fair value hedges:
	Corn futures			Other current assets			300			—			Other current assets			—			—
	Derivatives not designated as hedging instruments:
	Natural gas futures			Other current assets			3			—			Other current assets			—			—
						$	303		$	997					$	3,202		$	485
Effect of Derivative Instruments on Company's Financial Performance	'
	The following tables provide information about the effect of derivative instruments on the financial performance of the Company for the three- and nine-month periods ended May 31, 2014 and 2013:
	(In thousands)		Amount of Gain (Loss)						Amount of Gain (Loss)						Amount of Gain (Loss)
			Recognized in OCI						Reclassified from						Recognized in Income
									AOCI into Income
			3 Months Ended May 31,						3 Months Ended May 31,						3 Months Ended May 31,
			2014			2013			2014			2013			2014			2013
	Derivatives designated as hedging instruments:
	Cash flow hedges:
	Corn futures (1)		$	760		$	530		$	1,744		$	596		$	(198	)	$	(474	)
	Ethanol futures (1)			(4,128	)		(557	)		(5,760	)		(355	)		(260	)		—
			$	(3,368	)	$	(27	)	$	(4,016	)	$	241		$	(458	)	$	(474	)
	Fair value hedges:
	Corn futures (1) (2)														$	(21	)	$	143
	Derivatives not designated as hedging instruments:
	Natural gas futures (1)														$	(854	)	$	294
	Natural gas options (1)															—			(20	)
	Soybean meal futures (1)															5			—
															$	(849	)	$	274
	-1	Gains and losses reported in Cost of sales
	-2	Hedged items are firm commitments and inventory
	(In thousands)		Amount of Gain (Loss)						Amount of Gain (Loss)						Amount of Gain (Loss)
			Recognized in OCI						Reclassified from						Recognized in Income
									AOCI into Income
			9 Months Ended May 31,						9 Months Ended May 31,						9 Months Ended May 31,
			2014			2013			2014			2013			2014			2013
	Derivatives designated as hedging instruments:
	Cash flow hedges:
	Corn futures (1)		$	81		$	(43	)	$	(2,116	)	$	4,087		$	(1,595	)	$	(589	)
	Ethanol futures (1)			(9,688	)		429			(7,368	)		(71	)		(331	)		(11	)
			$	(9,607	)	$	386		$	(9,484	)	$	4,016		$	(1,926	)	$	(600	)
	Fair value hedges:
	Corn futures (1) (2)														$	75		$	127
	Derivatives not designated as hedging instruments:
	Natural gas futures (1)														$	(634	)	$	(16	)
	Natural gas options (1)															—			(20	)
	Soybean meal futures (1)															11
	Ethanol futures (1)															64			—
															$	(559	)	$	(36	)
	-1	Gains and losses reported in Cost of sales
	-2	Hedged items are firm commitments and inventory

Segment_Reporting_Tables

Segment Reporting (Tables)	9 Months Ended
	31-May-14
Segment Reporting [Abstract]	'
Segment Wide Reporting Information	'
	Three Months Ended May 31,						Nine Months Ended May 31,
	(In thousands)	2014			2013			2014			2013
	Sales:
	Industrial Ingredients:
	Industrial Starch	$	39,723		$	44,572		$	120,261		$	132,610
	Ethanol		27,952			28,111			72,966			69,710
	By-Products		16,437			20,501			47,312			64,710
			84,112			93,184			240,539			267,030
	Food Ingredients		35,317			28,535			94,247			82,793
		$	119,429		$	121,719		$	334,786		$	349,823
	Income (loss) from operations:
	Industrial Ingredients	$	1,957		$	565		$	(72	)	$	1,500
	Food Ingredients		6,025			6,206			18,349			17,097
	Corporate and other		(3,057	)		(2,496	)		(8,801	)		(7,772	)
		$	4,925		$	4,275		$	9,476		$	10,825
	(In thousands)	May 31,			August 31,
		2014			2013
	Total assets:
	Industrial Ingredients	$	136,020		$	133,120
	Food Ingredients		88,423			68,550
	Corporate and other		12,185			22,948
		$	236,628		$	224,618

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	9 Months Ended
	31-May-14
Earnings Per Share [Abstract]	'
Reconciliation of Income from Operations Applicable to Common Shares and Computation of Diluted Weighted Average Shares Outstanding	'
	The following table presents the reconciliation of income from operations to income from operations applicable to common shares and the computation of diluted weighted-average shares outstanding:
		Three Months Ended May 31,						Nine Months Ended May 31,
	(In thousands)	2014			2013			2014			2013
	Numerator:
	Net income	$	3,071		$	2,058		$	4,798		$	4,956
	Less: Allocation to participating securities		(16	)		(4	)		(14	)		(15	)
	Net income applicable to common shares	$	3,055		$	2,054		$	4,784		$	4,941
	Denominator:
	Weighted average common shares outstanding, basic		12,532			12,395			12,502			12,349
	Dilutive stock options and awards		343			275			345			199
	Weighted average common shares outstanding, diluted		12,875			12,670			12,847			12,548

Acquisition_Tables

Acquisition (Tables)	9 Months Ended
	31-May-14
Business Combinations [Abstract]	'
Schedule of Acquisition	'
	At May 31, 2014, the acquisition was reflected in the condensed consolidated financial statements as follows:
	(In thousands)
	Cash paid at closing	$	9,086
	Accrued liabilities:
	Working capital adjustment		72
	Holdback		750
	Total purchase price	$	9,908
Purchase Price Allocation to Assets Acquired and Liabilities Assumed	'
	The preliminary allocation of the purchase price to the assets acquired and liabilities assumed, based on their fair values as of March 25, 2014, is presented below.
	(In thousands)
	Working capital	$	2,133
	Non-competition agreement		490
	Customer relationships		2,600
	Trade name portfolio		2,700
	Goodwill		1,934
	Other assets		51
	Total purchase price	$	9,908

Business_Additional_Informatio

Business - Additional Information (Detail) (USD $)	9 Months Ended	0 Months Ended		1 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-14	Mar. 25, 2014	Mar. 31, 2014
	Segment	Gum Technology [Member]	Gum Technology [Member]	Gum Technology [Member]
Business Acquisition [Line Items]	'	'	'	'
Number of segments	2	'	'	'
Purchase price	'	$9,908	$9,908	$9,908

Basis_of_Presentation_Addition

Basis of Presentation - Additional Information (Detail) (Service Life [Member], USD $)	3 Months Ended
	31-May-14
Service Life [Member]	'
Change in Accounting Estimate [Line Items]	'
Effect of change in estimate on net income	$136,000
Increase in diluted earnings per share	$0.01

Balance_Sheet_Details_Componen

Balance Sheet Details - Components of Inventory (Detail) (USD $)	31-May-14	Aug. 31, 2013
In Thousands, unless otherwise specified
Inventory Disclosure [Abstract]	'	'
Raw materials	$9,453	$10,381
Work in progress	1,430	1,913
Finished goods	27,415	21,698
Total inventories	$38,298	$33,992

Balance_Sheet_Details_Componen1

Balance Sheet Details - Components of Property, Plant and Equipment (Detail) (USD $)	31-May-14	Aug. 31, 2013
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment, gross	$384,790	$377,045
Accumulated depreciation	-273,029	-264,904
Net property, plant and equipment	111,761	112,141
Land and land improvements [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment, gross	12,159	11,881
Plant and equipment [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment, gross	363,974	359,909
Construction in progress [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment, gross	$8,657	$5,255

Balance_Sheet_Details_Addition

Balance Sheet Details - Additional Information (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	31-May-14	Aug. 31, 2013
Property Plant And Equipment [Abstract]	'	'
Payables related to property, plant and equipment	$0.70	$0.70

Balance_Sheet_Details_Componen2

Balance Sheet Details - Components of Accrued Liabilities (Detail) (USD $)	31-May-14	Aug. 31, 2013
In Thousands, unless otherwise specified
Accrued Liabilities Current [Abstract]	'	'
Employee-related costs	$3,977	$3,931
Other accrued liabilities	5,096	4,276
Total accrued liabilities	$9,073	$8,207

Debt_Additional_Information_De

Debt - Additional Information (Detail) (2012 Agreement [Member], USD $)	9 Months Ended
	31-May-14
Debt Instrument [Line Items]	'
Maximum borrowing amount under amended and restated credit agreement	$130,000,000
Line of credit, amount outstanding	76,500,000
Debt instrument maturity date	9-Jul-17
Two Consecutive Quarters [Member]	'
Debt Instrument [Line Items]	'
Covenant, total leverage ratio restricting capital expenditures	2.5
Minimum [Member]	'
Debt Instrument [Line Items]	'
Debt instrument, variable interest rate percentage over LIBOR	2.00%
Covenant, fixed charge coverage ratio	1.35
Maximum [Member]	'
Debt Instrument [Line Items]	'
Debt instrument, variable interest rate percentage over LIBOR	4.00%
Covenant, total leverage ratio permitted	4.25
Covenant, amount of annual capital expenditures permitted	15,000,000
Covenant, dividend declaration permitted	10,000,000
Dividend declared, percentage of cash flow	50.00%
Maximum [Member] | Scenario, Forecast [Member]	'
Debt Instrument [Line Items]	'
Covenant, total leverage ratio permitted	3.5
Covenant, total leverage ratio permitted after August 31, 2014	3
Covenant, amount of annual capital expenditures permitted	$17,500,000

Debt_Iowa_Department_of_Econom

Debt - Iowa Department of Economic Development - Additional Information (Detail) (USD $)	9 Months Ended		0 Months Ended	1 Months Ended	3 Months Ended	9 Months Ended
	31-May-14	31-May-13	Dec. 01, 2009	31-May-14	31-May-14	31-May-14
			Iowa Department of Economic Development Loans [Member]	Iowa Department of Economic Development Loans [Member]	Iowa Department of Economic Development Loans [Member]	Iowa Department of Economic Development Loans [Member]
			SecurityLoan
Debt Instrument [Line Items]	'	'	'	'	'	'
Non interest bearing loans	'	'	$1,000,000	'	'	'
Number of monthly payments	'	'	'	'	'	'60 equal monthly payments
Number of non interest bearing loans	'	'	2	'	'	'
Loan period (in years)	'	'	'5 years	'	'	'
Potentially forgivable loan amount	'	'	1,000,000	'	'	'
Periodic repayments of loan	'	'	16,667	'	'	'
Repayment of outstanding balance	367,000	150,000	'	'	1,000,000	'
Forgivable loan amount forgiven	'	'	'	1,000,000	'	'
Loan forgiveness recorded as non-operating income	$1,000,000	'	'	$1,000,000	'	'

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended			9 Months Ended
	31-May-14	31-May-13	Feb. 28, 2013	31-May-14	31-May-13	Aug. 31, 2013	31-May-14
						Australian Operations [Member]	Small Ethanol Producer [Member]
Tax Credit Carryforward [Line Items]	'	'	'	'	'	'	'
Effective tax rate	38.60%	40.00%	'	39.60%	37.00%	'	'
Write-off of deferred tax assets related to expired stock option awards	'	$300,000	'	'	'	'	'
Tax benefit related to research and development activities	'	'	150,000	'	'	'	'
Impact on the effective tax rate related to tax credit for research and development	'	'	'	'	2.00%	'	'
Valuation allowance	'	'	'	'	'	10,900,000	1,800,000
Net deferred tax assets	1,800,000	'	'	1,800,000	'	'	'
Decrease in unrecognized tax benefits due to statute expirations	'	'	'	150,000	'	'	'
Total amount of gross unrecognized tax benefits, if recognized that would impact effective tax rate	600,000	'	'	600,000	'	'	'
Accrued interest and penalties included in long-term tax liability	$100,000	'	'	$100,000	'	'	'
Open tax year	'	'	'	'2009	'	'	'

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income (Loss) ("AOCI") - Summary of Changes in Accumulated Other Comprehensive Income (Loss) (Detail) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Beginning Balances	($7,619)	($15,593)
Other comprehensive income (loss) before reclassification adjustments, net of tax	-3,207	239
Amounts reclassified from Accumulated other comprehensive income (loss), net of tax	6,068	-1,426
Ending Balances	-4,758	-16,780
Cash Flow Hedging Instruments [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Beginning Balances	-856	1,638
Other comprehensive income (loss) before reclassification adjustments, net of tax	-5,912	239
Amounts reclassified from Accumulated other comprehensive income (loss), net of tax	5,842	-2,490
Ending Balances	-926	-613
Postretirement Obligations [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Beginning Balances	-6,763	-17,231
Other comprehensive income (loss) before reclassification adjustments, net of tax	2,705	'
Amounts reclassified from Accumulated other comprehensive income (loss), net of tax	226	1,064
Ending Balances	($3,832)	($16,167)

Accumulated_Other_Comprehensiv3

Accumulated Other Comprehensive Income (Loss) ("AOCI") - Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-14	31-May-13
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Amortization of actuarial loss (gain), Tax	$17	$209	$117	$627
Amortization of actuarial loss (gain), Net of Tax Amount	-28	-341	-190	-1,023
Amortization of prior service cost, Tax	8	8	24	25
Amortization of prior service cost, Net of Tax Amount	-12	-13	-36	-41
Before Tax Amount	-5,004	-3,423	-7,940	-7,831
Tax	1,933	1,365	3,142	2,875
Net of Tax Amount	-3,071	-2,058	-4,798	-4,956
Reclassification out of Accumulated Other Comprehensive Income [Member]	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Before Tax Amount	4,081	'	9,851	'
Tax	-1,567	'	-3,783	'
Net of Tax Amount	2,514	'	6,068	'
Reclassification out of Accumulated Other Comprehensive Income [Member] | Cost of sales [Member]	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Amortization of actuarial loss (gain), Before Tax Amount	45	'	223	'
Amortization of actuarial loss (gain), Tax	-17	'	-87	'
Amortization of actuarial loss (gain), Net of Tax Amount	28	'	136	'
Amortization of prior service cost, Before Tax Amount	20	'	24	'
Amortization of prior service cost, Tax	-8	'	-11	'
Amortization of prior service cost, Net of Tax Amount	12	'	13	'
Reclassification out of Accumulated Other Comprehensive Income [Member] | Operating/R&D expenses [Member]	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Amortization of actuarial loss (gain), Before Tax Amount	'	'	84	'
Amortization of actuarial loss (gain), Tax	'	'	-30	'
Amortization of actuarial loss (gain), Net of Tax Amount	'	'	54	'
Amortization of prior service cost, Before Tax Amount	0	'	36	'
Amortization of prior service cost, Tax	0	'	-13	'
Amortization of prior service cost, Net of Tax Amount	0	'	23	'
Postretirement Obligations [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Before Tax Amount	65	'	367	'
Tax	-25	'	-141	'
Net of Tax Amount	40	'	226	'
Cash Flow Hedging Instruments [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]	'	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Before Tax Amount	4,016	'	9,484	'
Tax	-1,542	'	-3,642	'
Net of Tax Amount	$2,474	'	$5,842	'

StockBased_Compensation_Additi

Stock-Based Compensation - Additional Information (Detail) (USD $)

9 Months Ended

0 Months Ended

9 Months Ended

0 Months Ended

3 Months Ended

0 Months Ended

9 Months Ended

31-May-14

31-May-14

Mar. 25, 2014

31-May-14

31-May-14

31-May-14

Jan. 01, 2014

31-May-14

Jan. 01, 2014

31-May-14

31-May-14

31-May-14

2006 Incentive Plan [Member]

Compensatory Stock Options [Member]

Stock Options [Member]

Stock Options [Member]

Restricted Stock [Member]

Restricted Stock [Member]

Restricted Stock [Member]

Restricted Stock [Member]

Non Qualified Stock Options And Restricted Stock [Member]

Non Qualified Stock Options And Restricted Stock [Member]

Non Qualified Stock Options And Restricted Stock [Member]

Gum Technology [Member]

2006 Incentive Plan [Member]

2006 Incentive Plan [Member]

2006 Incentive Plan [Member]

2006 Incentive Plan [Member]

2006 Incentive Plan [Member]

2006 Incentive Plan [Member]

2006 Incentive Plan [Member]

Employees

Non Employee Directors [Member]

Minimum [Member]

Maximum [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Number of common shares available for issuance under the plan

'

186,542

'

'

'

'

'

'

'

'

'

'

Vesting period (in years)

'

'

'3 years

'

'

'

'

'3 years

'1 year

'

'1 year

'4 years

Expiration period (in years)

'

'

'7 years

'

'

'

'

'

'

'7 years

'

'

Share price of Company's stock

$11.98

'

'

'

'

'

'

'

'

'

'

'

Intrinsic value of options exercised

$327,200

'

'

'

'

'

'

'

'

'

'

'

Stock options granted, shares

71,000

'

45,000

'

26,000

'

'

'

'

'

'

'

Number of key former employees

'

'

3

'

'

'

'

'

'

'

'

'

Compensation expense related to non-vested awards not yet recognized

'

'

'

700,000

'

'

'

'

'

'

'

'

Weighted-average period over which unrecognized compensation cost will be recognized (in years)

'

'

'

'1 year 3 months 18 days

'

'1 year 6 months

'

'

'

'

'

'

Compensation expense related to unvested awards not yet recognized

'

'

'

'

'

$2,000,000

'

'

'

'

'

'

Restricted stock awards granted (in shares)

'

'

'

'

'

'

15,560

157,500

1,556

'

'

'

StockBased_Compensation_Schedu

Stock-Based Compensation - Schedule of Share Based Compensation Stock Options Activity (Detail) (USD $)	9 Months Ended
	31-May-14
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Options outstanding, beginning of period, Shares	1,517,588
Shares, Granted	71,000
Shares, Exercised	-52,500
Shares, Cancelled	-84,817
Options outstanding, end of period, Shares	1,451,271
Options exercisable, end of period, Shares	1,104,773
Weighted-Average Exercise Price, Options Outstanding beginning of period, Per Share	$10.30
Weighted-Average Exercise Price, Granted, Per Share	$13.53
Weighted-Average Exercise Price, Exercised, Per Share	$6.62
Weighted-Average Exercise Price, Cancelled, Per Share	$15.20
Weighted-Average Exercise Price, Options Outstanding end of period, Per Share	$10.30
Weighted-Average Exercise Price, Options exercisable, end of period, Per Share	$11.11
Weighted Average Remaining Term, Outstanding, Ending balance (in years)	'3 years 4 months 28 days
Weighted Average Remaining Term, Options exercisable (in years)	'2 years 10 months 2 days
Aggregate Intrinsic value, Outstanding, Ending balance	$4,985,200
Aggregate Intrinsic value, Options exercisable	$3,397,600

StockBased_Compensation_Schedu1

Stock-Based Compensation - Schedule of Share Based Payment Award Stock Options Valuation Assumptions (Detail) (Stock Options [Member], USD $)	9 Months Ended
	31-May-14
Stock Options [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Expected volatility	56.00%
Expected life (years)	'5 years
Interest rate, minimum	1.10%
Interest rate, maximum	2.10%
Weighted-average fair values	$6.53

StockBased_Compensation_Schedu2

Stock-Based Compensation - Schedule of Share-Based Compensation, Restricted Stock Award Activity (Detail) (Restricted Stock [Member], USD $)	9 Months Ended
	31-May-14
Restricted Stock [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Shares, Nonvested at August 31, 2013	24,489
Shares, Granted	173,060
Shares, Vested	-24,489
Shares, Cancelled	'
Shares, Nonvested at May 31, 2014	173,060
Weighted-Average Grant-Date Fair Value, Beginning balance (in USD per share)	$7.35
Weighted-Average Grant-Date Fair Value, Granted (in USD per share)	$12.64
Weighted-Average Grant-Date Fair Value, Vested (in USD per share)	$7.35
Weighted-Average Grant-Date Fair Value, Cancelled (in USD per share)	'
Weighted-Average Grant-Date Fair Value, Ending balance (in USD per share)	$12.64

StockBased_Compensation_Schedu3

Stock-Based Compensation - Schedule of Employee Service Share-Based Compensation, Allocation of Recognized Period Costs (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-14	31-May-13
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Total stock-based compensation expense	$326	$290	$841	$1,102
Income tax benefit	125	110	323	419
Total stock-based compensation expense, net of tax	201	180	518	683
Cost of sales [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Total stock-based compensation expense	4	'	4	'
Operating expenses [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Total stock-based compensation expense	320	290	835	1,102
Research and development expenses [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Total stock-based compensation expense	$2	'	$2	'

Pension_and_PostRetirement_Ben2

Pension and Post-Retirement Benefit Plans - Components of Net Periodic Benefit Costs (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-14	31-May-13
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Net periodic benefit cost	'	'	$1,300	'
Defined Benefit Pension Plans [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Service cost	237	486	1,113	1,458
Interest cost	698	662	2,168	1,986
Expected return on plan assets	-873	-717	-2,499	-2,151
Amortization of prior service cost	58	60	174	180
Amortization of actuarial losses	45	483	307	1,449
Net periodic benefit cost	165	974	1,263	2,922
Post-retirement Health Care Plans [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Service cost	28	59	84	177
Interest cost	222	215	666	645
Amortization of prior service cost	-38	-38	-114	-114
Amortization of actuarial losses	'	67	'	201
Net periodic benefit cost	$212	$303	$636	$909

Pension_and_PostRetirement_Ben3

Pension and Post-Retirement Benefit Plans - Additional Information (Detail) (USD $)	0 Months Ended	9 Months Ended
	Aug. 31, 2013	31-May-14
Defined Benefit Plan Disclosure [Line Items]	'	'
Discount rate	4.91%	'
Decrease in pension net periodic benefit cost	'	$400,000
Employer contribution to defined benefit pension plans	'	1,800,000
Return on plan assets	'	3,400,000
Curtailment gain	'	2,700,000
Actuarial losses	'	900,000
Net periodic benefit cost	'	$1,300,000
Prior To Amendment [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Discount rate	5.24%	'

Fair_Value_Measurements_and_De2

Fair Value Measurements and Derivative Instruments - Fair Values of Company's Derivative Instruments (Detail) (Commodity Contract [Member], USD $)	31-May-14	Aug. 31, 2013
In Thousands, unless otherwise specified
Derivative [Line Items]	'	'
Commodity derivatives	($2,899)	$512
Other current assets [Member]	'	'
Derivative [Line Items]	'	'
Commodity derivatives	-2,899	512
Level 1 [Member] | Other current assets [Member]	'	'
Derivative [Line Items]	'	'
Commodity derivatives	-2,899	512
Level 2 [Member] | Other current assets [Member]	'	'
Derivative [Line Items]	'	'
Commodity derivatives	'	'
Level 3 [Member] | Other current assets [Member]	'	'
Derivative [Line Items]	'	'
Commodity derivatives	'	'

Fair_Value_Measurements_and_De3

Fair Value Measurements and Derivative Instruments - Reconciliation of Gross Fair Value of Assets and Liabilities Subject to Offsetting Arrangements (Detail) (USD $)	31-May-14	Aug. 31, 2013
In Thousands, unless otherwise specified
Derivative Instruments and Hedging Activities Disclosures [Line Items]	'	'
Gross Amounts of Recognized Assets	$303	$997
Gross Liabilities Offset in the Balance Sheets	-3,202	-485
Commodity Contract [Member]	'	'
Derivative Instruments and Hedging Activities Disclosures [Line Items]	'	'
Gross Amounts of Recognized Assets	303	997
Gross Liabilities Offset in the Balance Sheets	-3,202	-485
Net Amount of Assets (Liabilities)	-2,899	512
Cash Collateral on Deposit with Counterparty	5,343	1,700
Net Fair Value as Recorded in Balance Sheets	$2,444	$2,212

Fair_Value_Measurements_and_De4

Fair Value Measurements and Derivative Instruments - Additional Information (Detail) (Commodity Contract [Member], USD $)	31-May-14
In Millions, unless otherwise specified
Commodity Contract [Member]	'
Fair Value, Option, Quantitative Disclosures [Line Items]	'
Deferred loss, net of tax, recorded in accumulated other comprehensive income	$0.90

Fair_Value_Measurements_and_De5

Fair Value Measurements and Derivative Instruments - Outstanding Futures Contracts (Detail) (Designated as Hedging Instrument [Member], Commodity Contract [Member])	31-May-14
	bu
Corn futures [Member]	'
Derivative [Line Items]	'
Outstanding futures contracts	4,775,000
Ethanol futures [Member]	'
Derivative [Line Items]	'
Outstanding futures contracts	14,700,000
Natural gas futures [Member]	'
Derivative [Line Items]	'
Outstanding futures contracts	40,000

Fair_Value_Measurements_and_De6

Fair Value Measurements and Derivative Instruments - Fair Value of Company's Derivatives by Contract Type (Detail) (USD $)	31-May-14	Aug. 31, 2013
In Thousands, unless otherwise specified
Derivatives, Fair Value [Line Items]	'	'
Assets Fair Value	$303	$997
Liabilities Fair Value	3,202	485
Commodity Contract [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Assets Fair Value	303	997
Liabilities Fair Value	3,202	485
Commodity Contract [Member] | Corn futures [Member] | Cash flow hedges [Member] | Designated as Hedging Instrument [Member] | Other current assets [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Assets Fair Value	'	'
Liabilities Fair Value	788	485
Commodity Contract [Member] | Corn futures [Member] | Fair value hedges [Member] | Designated as Hedging Instrument [Member] | Other current assets [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Assets Fair Value	300	'
Liabilities Fair Value	'	'
Commodity Contract [Member] | Ethanol futures [Member] | Cash flow hedges [Member] | Designated as Hedging Instrument [Member] | Other current assets [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Assets Fair Value	'	997
Liabilities Fair Value	2,414	'
Commodity Contract [Member] | Natural gas futures [Member] | Derivative Not Designated as Hedging Instruments [Member] | Other current assets [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Assets Fair Value	3	'
Liabilities Fair Value	'	'

Fair_Value_Measurements_and_De7

Fair Value Measurements and Derivative Instruments - Effect of Derivative Instruments on Company's Financial Performance (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-14	31-May-13
Designated as Hedging Instrument [Member] | Cash flow hedges [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Amount of Gain (Loss) Recognized in OCI	($3,368)	($27)	($9,607)	$386
Amount of Gain (Loss) Reclassified from AOCI into Income	-4,016	241	-9,484	4,016
Amount of Gain (Loss) Recognized in Income	-458	-474	-1,926	-600
Designated as Hedging Instrument [Member] | Cash flow hedges [Member] | Corn futures [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Amount of Gain (Loss) Recognized in OCI	760	530	81	-43
Amount of Gain (Loss) Reclassified from AOCI into Income	1,744	596	-2,116	4,087
Amount of Gain (Loss) Recognized in Income	-198	-474	-1,595	-589
Designated as Hedging Instrument [Member] | Cash flow hedges [Member] | Ethanol futures [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Amount of Gain (Loss) Recognized in OCI	-4,128	-557	-9,688	429
Amount of Gain (Loss) Reclassified from AOCI into Income	-5,760	-355	-7,368	-71
Amount of Gain (Loss) Recognized in Income	-260	'	-331	-11
Designated as Hedging Instrument [Member] | Fair value hedges [Member] | Corn futures [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Amount of Gain (Loss) Recognized in Income	-21	143	75	127
Derivative Not Designated as Hedging Instruments [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Amount of Gain (Loss) Recognized in Income	-849	274	-559	-36
Derivative Not Designated as Hedging Instruments [Member] | Ethanol futures [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Amount of Gain (Loss) Recognized in Income	'	'	64	'
Derivative Not Designated as Hedging Instruments [Member] | Natural gas futures [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Amount of Gain (Loss) Recognized in Income	-854	294	-634	-16
Derivative Not Designated as Hedging Instruments [Member] | Natural gas options [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Amount of Gain (Loss) Recognized in Income	'	-20	'	-20
Derivative Not Designated as Hedging Instruments [Member] | Soybean meal futures [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Amount of Gain (Loss) Recognized in Income	$5	'	$11	'

Segment_Reporting_Additional_I

Segment Reporting - Additional Information (Detail)	9 Months Ended
	31-May-14
	Segment
Segment Reporting [Abstract]	'
Number of segments	2

Segment_Reporting_Segment_Wide

Segment Reporting - Segment Wide Reporting Information (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-14	31-May-13	Aug. 31, 2013
Segment Reporting Information [Line Items]	'	'	'	'	'
Sales	$119,429	$121,719	$334,786	$349,823	'
Income (loss) from operations	4,925	4,275	9,476	10,825	'
Total assets	236,628	'	236,628	'	224,618
Industrial Ingredients [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Sales	84,112	93,184	240,539	267,030	'
Food Ingredients [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Sales	35,317	28,535	94,247	82,793	'
Industrial Starch [Member] | Industrial Ingredients [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Sales	39,723	44,572	120,261	132,610	'
Ethanol [Member] | Industrial Ingredients [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Sales	27,952	28,111	72,966	69,710	'
By-Products [Member] | Industrial Ingredients [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Sales	16,437	20,501	47,312	64,710	'
Operating Segments [Member] | Industrial Ingredients [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Income (loss) from operations	1,957	565	-72	1,500	'
Total assets	136,020	'	136,020	'	133,120
Operating Segments [Member] | Food Ingredients [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Income (loss) from operations	6,025	6,206	18,349	17,097	'
Total assets	88,423	'	88,423	'	68,550
Corporate, Non-Segment [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Income (loss) from operations	-3,057	-2,496	-8,801	-7,772	'
Total assets	$12,185	'	$12,185	'	$22,948

Earnings_Per_Share_Reconciliat

Earnings Per Share - Reconciliation of Income from Operations Applicable to Common Shares and Computation of Diluted Weighted Average Shares Outstanding (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-13	31-May-14	31-May-13
Numerator:	'	'	'	'
Net income	$3,071	$2,058	$4,798	$4,956
Less: Allocation to participating securities	-16	-4	-14	-15
Net income applicable to common shares	$3,055	$2,054	$4,784	$4,941
Denominator:	'	'	'	'
Weighted average common shares outstanding, basic	12,532	12,395	12,502	12,349
Dilutive stock options and awards	343	275	345	199
Weighted average common shares outstanding, diluted	12,875	12,670	12,847	12,548

Earnings_Per_Share_Additional_

Earnings Per Share - Additional Information (Detail) (Stock Options [Member])	3 Months Ended		9 Months Ended
	31-May-14	31-May-13	31-May-14	31-May-13
Stock Options [Member]	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Antidilutive weighted average stock options excluded from the calculation of diluted earnings per share	613,462	916,463	614,125	967,820

Legal_Proceedings_and_Continge1

Legal Proceedings and Contingencies - Additional Information (Detail) (USD $)	1 Months Ended	9 Months Ended		1 Months Ended	9 Months Ended
	Apr. 30, 2012	31-May-14	31-May-14	Mar. 31, 2014	31-May-14
	Patents	Defendants	Penford Products [Member]	Carolina Starches, LLC [Member]	Carolina Starches, LLC [Member]
Loss Contingencies [Line Items]	'	'	'	'	'
Number of patents under allegation of patent infringement	2	'	'	'	'
Number of defendants	'	2	'	'	'
Name of defendants	'	'Penford Products and Carolina Starches, LLC	'	'	'
Name of plaintiff	'	'Pirinate Consulting Group, LLC	'	'	'
Amount of recovery sought in complaint	'	'	$778,000	'	$216,000
Payment for full and final settlement of litigation	'	'	'	$10,000	'

Acquisition_Additional_Informa

Acquisition - Additional Information (Detail) (USD $)	0 Months Ended		1 Months Ended	3 Months Ended	9 Months Ended
	31-May-14	Mar. 25, 2014	Mar. 31, 2014	31-May-14	31-May-14
Business Acquisition [Line Items]	'	'	'	'	'
Stock options granted, shares	'	'	'	'	71,000
Non-competition agreement [Member]	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Amortization period	'	'	'	'	'5 years
Customer relationships [Member]	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Amortization period	'	'	'	'	'13 years
Gum Technology [Member]	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Total purchase price	$9,908,000	$9,908,000	$9,908,000	'	'
Purchase price held for post-closing obligations	'	750,000	'	'	'
Acquisition costs	'	86,000	'	'	'
Sales	'	'	'	$2,100,000	$2,100,000
Gum Technology [Member] | Compensatory Stock Options [Member]	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Number of key former employees	'	3	'	'	'
Stock options granted, shares	'	45,000	'	'	'
Contractual term of options	'	'7 years	'	'	'
Vesting period (in years)	'	'3 years	'	'	'
Gum Technology [Member] | Holdback [Member]	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Number of installments	'	2	'	'	'
First Installment [Member] | Gum Technology [Member]	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Holdback repayable period	'	'12 months	'	'	'
Second Installment [Member] | Gum Technology [Member]	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Holdback repayable period	'	'6 months	'	'	'

Acquisition_Schedule_of_Acquis

Acquisition - Schedule of Acquisition (Detail) (USD $)	9 Months Ended	0 Months Ended		1 Months Ended	0 Months Ended
In Thousands, unless otherwise specified	31-May-14	31-May-14	Mar. 25, 2014	Mar. 31, 2014	31-May-14	31-May-14
		Gum Technology [Member]	Gum Technology [Member]	Gum Technology [Member]	Gum Technology [Member]	Gum Technology [Member]
					Working capital adjustment [Member]	Holdback [Member]
Business Acquisition [Line Items]	'	'	'	'	'	'
Cash paid at closing	$9,086	$9,086	'	'	'	'
Accrued liabilities	'	'	'	'	72	750
Total purchase price	'	$9,908	$9,908	$9,908	'	'

Acquisition_Purchase_Price_All

Acquisition - Purchase Price Allocation to Assets Acquired and Liabilities Assumed (Detail) (USD $)	31-May-14	Aug. 31, 2013	Mar. 25, 2014	Mar. 25, 2014	Mar. 25, 2014
In Thousands, unless otherwise specified			Gum Technology [Member]	Gum Technology [Member]	Gum Technology [Member]
				Non-competition agreement [Member]	Customer relationships [Member]
Business Acquisition [Line Items]	'	'	'	'	'
Working capital	'	'	$2,133	'	'
Finite lived intangible assets	'	'	'	490	2,600
Trade name portfolio	'	'	2,700	'	'
Goodwill	9,912	7,978	1,934	'	'
Other assets	'	'	51	'	'
Total purchase price	'	'	$9,908	'	'