Commercial Metals (CMC) 10-Q 9 Jan 14 2014 Q1 Quarterly report Financial data

Document_And_Entity_Informatio

Document And Entity Information	3 Months Ended
	Nov. 30, 2013	Jan. 03, 2014
Entity Information [Line Items]	'	'
Trading Symbol	'CMC	'
Entity Registrant Name	'COMMERCIAL METALS CO	'
Entity Central Index Key	'0000022444	'
Document Type	'10-Q	'
Document Period End Date	30-Nov-13	'
Amendment Flag	'false	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q1	'
Current Fiscal Year End Date	'--08-31	'
Entity Tax Identification Number	'750725338	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Current Reporting Status	'Yes	'
Entity Common Stock, Shares Outstanding	'	117,310,716

Consolidated_Statements_Of_Ope

Consolidated Statements Of Operations (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Net sales	$1,682,891	$1,749,515
Costs and expenses:	'	'
Cost of goods sold	1,501,798	1,562,850
Selling, general and administrative expenses	114,463	124,609
Interest expense	19,578	17,024
Gain on sale of cost method investment	0	-26,088
Total costs and expenses	1,635,839	1,678,395
Earnings from continuing operations before income taxes	47,052	71,120
Income taxes	15,091	22,189
Earnings from continuing operations	31,961	48,931
Earnings from discontinued operations before income taxes	22,845	1,250
Income taxes	8,887	462
Earnings from discontinued operations	13,958	788
Net earnings	45,919	49,719
Less net earnings attributable to noncontrolling interests	0	2
Net earnings attributable to CMC	$45,919	$49,717
Basic earnings per share attributable to CMC:	'	'
Earnings from continuing operations	$0.27	$0.42
Earnings from discontinued operations	$0.12	$0.01
Net earnings	$0.39	$0.43
Diluted earnings per share attributable to CMC:	'	'
Earnings from continuing operations	$0.27	$0.42
Earnings from discontinued operations	$0.12	$0
Net earnings	$0.39	$0.42
Cash dividends per share	$0.12	$0.12
Average basic shares outstanding	117,070,499	116,336,504
Average diluted shares outstanding	118,156,611	117,093,627

Consolidated_Statements_Of_Com

Consolidated Statements Of Comprehensive Income (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Net earnings	$45,919	$49,719
Other comprehensive income, net of income taxes:	'	'
Foreign currency translation adjustment and other, net of income taxes of $2,077 and $11,792	19,442	21,900
Net unrealized gain (loss) on derivatives:	'	'
Unrealized holding gain (loss), net of income taxes of $(449) and $88	-1,617	317
Reclassification for loss (gain) included in net earnings, net of income taxes of $181 and $(49)	980	-122
Net unrealized gain (loss) on derivatives, net of income taxes of $(268) and $39	-637	195
Defined benefit obligation:	'	'
Net gain, net of income taxes of $296 and $0	550	0
Amortization of prior service cost (credit), net of income taxes of $(1) and $0	-2	2
Adjustment from plan changes, net of income taxes of $0 and $308	0	1,315
Defined benefit obligation, net of income taxes of $295 and $308	548	1,317
Other comprehensive income	19,353	23,412
Comprehensive income	$65,272	$73,131

Consolidated_Statements_Of_Com1

Consolidated Statements Of Comprehensive Income (Parenthetical) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Income taxes, foreign currency translation adjustment and other	$2,077	$11,792
Income taxes, unrealized holding gain (loss) on derivatives	-449	88
Income taxes, reclassification for loss (gain) on derivatives included in net earnings	181	-49
Income taxes, net unrealized gain (loss) on derivatives	-268	39
Income taxes, net gain of defined benefit obligation	296	0
Income taxes, amortization of prior service cost (credit) of defined benefit obligation	-1	0
Income taxes, adjustment from plan changes of defined benefit obligation	0	308
Income taxes, defined benefit obligation	$295	$308

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Nov. 30, 2013	Aug. 31, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$515,473	$378,770
Accounts receivable (less allowance for doubtful accounts of $9,773 and $10,042)	927,100	989,694
Inventories, net	792,763	757,417
Other	180,756	240,314
Total current assets	2,416,092	2,366,195
Property, plant and equipment:	'	'
Land	80,810	80,764
Buildings and improvements	494,256	486,494
Equipment	1,685,480	1,666,250
Construction in process	19,620	18,476
Property, plant and equipment, Gross	2,280,166	2,251,984
Less accumulated depreciation and amortization	-1,349,814	-1,311,747
Property, plant and equipment, Net	930,352	940,237
Goodwill	69,733	69,579
Other assets	121,532	118,790
Total assets	3,537,709	3,494,801
Current liabilities:	'	'
Accounts payable-trade	347,354	342,678
Accounts payable-documentary letters of credit	131,412	112,281
Accrued expenses and other payables	269,889	314,949
Notes payable	7,993	5,973
Current maturities of long-term debt	6,232	5,228
Total current liabilities	762,880	781,109
Deferred income taxes	53,838	46,558
Other long-term liabilities	120,542	118,165
Long-term debt	1,277,303	1,278,814
Total liabilities	2,214,563	2,224,646
Commitments and contingencies	'	'
Stockholders' equity:	'	'
Common stock, par value $0.01 per share; authorized 200,000,000 shares; issued 129,060,664 shares; outstanding 117,304,487 and 117,010,990 shares	1,290	1,290
Additional paid-in capital	359,765	363,772
Accumulated other comprehensive loss	-7,823	-27,176
Retained earnings	1,198,584	1,166,732
Less treasury stock, 11,756,177 and 12,049,674 shares at cost	-228,744	-234,619
Stockholders' equity attributable to CMC	1,323,072	1,269,999
Stockholders' equity attributable to noncontrolling interests	74	156
Total stockholders' equity	1,323,146	1,270,155
Total liabilities and stockholders' equity	$3,537,709	$3,494,801

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Nov. 30, 2013	Aug. 31, 2013
In Thousands, except Share data, unless otherwise specified
Allowance for doubtful accounts	$9,773	$10,042
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	129,060,664	129,060,664
Common stock, shares outstanding	117,304,487	117,010,990
Treasury stock, shares	11,756,177	12,049,674

Consolidated_Statements_Of_Cas

Consolidated Statements Of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Cash flows from (used by) operating activities:	'	'
Net earnings	$45,919	$49,719
Adjustments to reconcile net earnings to cash flows from (used by) operating activities:	'	'
Depreciation and amortization	33,860	33,751
Provision for losses on receivables, net	-240	1,153
Share-based compensation	5,544	4,509
Amortization of interest rate swaps termination gain	-1,900	-2,908
Deferred income taxes (benefit)	19,081	23,876
Tax benefits from stock plans	-109	0
Net gain on sale of a subsidiary, cost method investment and other	-25,064	-26,071
Asset impairment	1,005	3,028
Changes in operating assets and liabilities:	'	'
Accounts receivable	73,052	81,217
Accounts receivable sold, net	3,327	-46,614
Inventories	-29,789	-99,076
Other assets	-20,185	-740
Accounts payable, accrued expenses and other payables	-31,534	-56,228
Other long-term liabilities	505	113
Net cash flows from (used by) operating activities	73,472	-34,271
Cash flows from (used by) investing activities:	'	'
Capital expenditures	-14,085	-24,757
Proceeds from the sale of property, plant and equipment and other	2,126	5,956
Proceeds from the sale of a subsidiary	54,265	0
Proceeds from the sale of cost method investment	0	28,995
Net cash flows from (used by) investing activities	42,306	10,194
Cash flows from (used by) financing activities:	'	'
Increase in documentary letters of credit	18,663	60,217
Short-term borrowings, net change	2,020	-13,045
Repayments on long-term debt	-1,551	-1,284
Payments for debt issuance costs	-430	0
Decrease in restricted cash	17,300	0
Stock issued under incentive and purchase plans, net of forfeitures	-2,089	-414
Cash dividends	-14,067	-13,963
Tax benefits from stock plans	109	0
Contribution from (purchase of) noncontrolling interests	-52	15
Net cash flows from (used by) financing activities	19,903	31,526
Effect of exchange rate changes on cash	1,022	1,525
Increase in cash and cash equivalents	136,703	8,974
Cash and cash equivalents at beginning of year	378,770	262,422
Cash and cash equivalents at end of period	$515,473	$271,396

Consolidated_Statements_Of_Sto

Consolidated Statements Of Stockholders' Equity (USD $)	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Treasury Stock	Noncontrolling Interests
In Thousands, except Share data
Beginning balance at Aug. 31, 2012	$1,246,507	$1,290	$365,778	($18,136)	$1,145,445	($248,009)	$139
Beginning balance, treasury stock, shares at Aug. 31, 2012	'	'	'	'	'	-12,709,240	'
Beginning balance, shares at Aug. 31, 2012	'	129,060,664	'	'	'	'	'
Net earnings	49,719	'	'	'	49,717	'	2
Other comprehensive loss	23,412	'	'	23,412	'	'	'
Cash dividends	-13,963	'	'	'	-13,963	'	'
Issuance of stock under incentive and purchase plans, net of forfeitures	-414	'	-2,523	'	'	2,109	'
Issuance of stock under incentive and purchase plans, net of forfeitures, shares	'	'	'	'	'	97,474	'
Share-based compensation	3,081	'	3,081	'	'	'	'
Tax benefits from stock plans	0	'	'	'	'	'	'
Contribution from (purchase of) noncontrolling interests	15	'	'	'	'	'	15
Ending balance at Nov. 30, 2012	1,308,357	1,290	366,336	5,276	1,181,199	-245,900	156
Ending balance, treasury stock, shares at Nov. 30, 2012	'	'	'	'	'	-12,611,766	'
Ending balance, shares at Nov. 30, 2012	'	129,060,664	'	'	'	'	'
Beginning balance at Aug. 31, 2013	1,270,155	1,290	363,772	-27,176	1,166,732	-234,619	156
Beginning balance, treasury stock, shares at Aug. 31, 2013	-12,049,674	'	'	'	'	-12,049,674	'
Beginning balance, shares at Aug. 31, 2013	129,060,664	129,060,664	'	'	'	'	'
Net earnings	45,919	'	'	'	45,919	'	'
Other comprehensive loss	19,353	'	'	19,353	'	'	'
Cash dividends	-14,067	'	'	'	-14,067	'	'
Issuance of stock under incentive and purchase plans, net of forfeitures	-2,089	'	-7,964	'	'	5,875	'
Issuance of stock under incentive and purchase plans, net of forfeitures, shares	'	'	'	'	'	293,497	'
Share-based compensation	3,818	'	3,818	'	'	'	'
Tax benefits from stock plans	109	'	109	'	'	'	'
Contribution from (purchase of) noncontrolling interests	-52	'	30	'	'	'	-82
Ending balance at Nov. 30, 2013	$1,323,146	$1,290	$359,765	($7,823)	$1,198,584	($228,744)	$74
Ending balance, treasury stock, shares at Nov. 30, 2013	-11,756,177	'	'	'	'	-11,756,177	'
Ending balance, shares at Nov. 30, 2013	129,060,664	129,060,664	'	'	'	'	'

Accounting_Policies

Accounting Policies	3 Months Ended
	Nov. 30, 2013
Accounting Policies [Abstract]	'
Accounting policies	'
	NOTE 1. ACCOUNTING POLICIES
	Accounting Principles
	The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States ("GAAP") on a basis consistent with that used in the Annual Report on Form 10-K filed by Commercial Metals Company ("CMC", and together with its consolidated subsidiaries, the "Company") with the Securities and Exchange Commission ("SEC") for the year ended August 31, 2013, and include all normal recurring adjustments necessary to present fairly the consolidated balance sheets and the consolidated statements of operations, comprehensive income, cash flows and stockholders' equity for the periods indicated. These notes should be read in conjunction with the audited consolidated financial statements and notes included in the Annual Report on Form 10-K for the year ended August 31, 2013. The results of operations for the three month period are not necessarily indicative of the results to be expected for the full year.
	Recent Accounting Pronouncements
	In the first quarter of fiscal 2014, the Company adopted guidance issued by the Financial Accounting Standards Board ("FASB") requiring an entity to provide quantitative and qualitative disclosures about the nature of its rights of setoff and related arrangements associated with its financial instruments and derivative instruments. The objective is to make financial statements that are prepared under GAAP more comparable to those prepared under International Financial Reporting Standards. The new disclosures will give financial statement users information about both gross and net exposures. The adoption of this guidance did not have a material impact on the Company's consolidated financial statements.
	In July 2013, the FASB issued guidance requiring entities to net an unrecognized tax benefit with a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward. To the extent a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. The new guidance is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2013. The Company does not expect this guidance to have a material impact on its consolidated financial statements.
	In April 2013, the FASB issued guidance requiring an entity to prepare its financial statements using the liquidation basis of accounting when liquidation is imminent. In addition, the guidance provides principles for the recognition and measurement of assets and liabilities and requirements for financial statements prepared using the liquidation basis of accounting. The new guidance is effective prospectively for entities that determine liquidation is imminent during fiscal years, and interim reporting periods within those years, beginning after December 15, 2013. The Company does not expect this guidance to have a material impact on its consolidated financial statements.
	In March 2013, the FASB issued guidance requiring an entity to release any related cumulative translation adjustment into net income when it either sells a part or all of its investment in a foreign entity or no longer holds a controlling financial interest in a subsidiary or group of assets that is a nonprofit activity or a business within a foreign entity. In addition, the guidance resolves the diversity in practice for the treatment of business combinations achieved in stages involving a foreign entity. The new guidance is effective prospectively for fiscal years, and interim reporting periods within those years, beginning after December 15, 2013. The Company does not expect the adoption of this guidance to have a material impact on its consolidated financial statements.
	In February 2013, the FASB issued guidance requiring an entity to measure obligations resulting from joint and several liability arrangements for which the total amount of the obligation is fixed at the reporting date. The guidance also requires entities to disclose the nature and amount of the obligation as well as other information about the obligation. The new guidance is effective retrospectively for fiscal years, and interim reporting periods within those years, beginning after December 15, 2013. The Company does not expect the adoption of this guidance to have a material impact on its consolidated financial statements.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Income (Loss)	3 Months Ended
	Nov. 30, 2013
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'
Accumulated Other Comprehensive Income (Loss)	'
	NOTE 2. ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)
	Accumulated other comprehensive income (loss), net of income taxes, is comprised of the following:
	(in thousands)	Foreign Currency Translation				Unrealized Gain (Loss) on Derivatives			Defined Benefit Obligation			Total Accumulated Other Comprehensive Income (Loss)
	Balance, August 31, 2013	$	(27,477	)		$	3,594		$	(3,293	)	$	(27,176	)
	Other comprehensive income (loss) before reclassifications	19,442				(1,617		)	550			18,375
	Amounts reclassified from AOCI	—				980			(2		)	978
	Net other comprehensive income (loss)	19,442				(637		)	548			19,353
	Balance, November 30, 2013	$	(8,035	)		$	2,957		$	(2,745	)	$	(7,823	)
	The significant items reclassified out of accumulated other comprehensive income (loss) and the corresponding line items in the consolidated statements of operations to which the items were reclassified were as follows:
	Components of AOCI (in thousands)	Location		Three Months Ended November 30, 2013
	Unrealized gain (loss) on derivatives:
	Commodity	Cost of goods sold		$	(119	)
	Foreign exchange	Net sales		(250		)
	Foreign exchange	Cost of goods sold		(922		)
	Foreign exchange	SG&A expenses		14
	Interest rate	Interest expense		116
				(1,161		)
	Income tax effect	Income taxes (expense) benefit		181
	Net of income taxes			$	(980	)
	Defined benefit obligation:
	Amortization of net gain	SG&A expenses		$	3
	Income tax effect	Income taxes (expense) benefit		(1		)
	Net of income taxes			$	2
	Amounts in parentheses reduce earnings.

Sales_Of_Accounts_Receivable

Sales Of Accounts Receivable	3 Months Ended
	Nov. 30, 2013
Transfers and Servicing [Abstract]	'
Sales of accounts receivable	'
	NOTE 3. SALES OF ACCOUNTS RECEIVABLE
	The Company has a domestic sale of accounts receivable program which expires on December 26, 2014. Under the program, Commercial Metals Company contributes, and several of its subsidiaries sell without recourse, certain eligible trade accounts receivable to CMC Receivables, Inc. ("CMCRV"), a wholly owned subsidiary of CMC. CMCRV is structured to be a bankruptcy-remote entity and was formed for the sole purpose of buying and selling receivables generated by the Company. CMCRV sells the trade accounts receivable in their entirety to two financial institutions. The financial institutions advance up to a maximum of $200 million for all receivables sold, and the remaining portion of the purchase price of the receivables will be paid to the Company from the ultimate collection of the receivables after payment of certain fees and other costs. The Company accounts for sales of the receivables as true sales and the trade accounts receivable balances that are sold are removed from the consolidated balance sheets. The cash advances received are reflected as cash provided by operating activities on the Company's consolidated statements of cash flows. Additionally, the receivables program contains certain cross-default provisions whereby a termination event could occur if the Company defaulted under certain of its credit arrangements. The covenants contained in the receivables purchase agreement are consistent with the credit facility described in Note 7, Credit Arrangements.
	At November 30, 2013 and August 31, 2013, under its domestic sale of accounts receivable program, the Company had sold $356.9 million and $358.8 million of receivables, respectively, to the financial institutions and received no advance payments.
	In addition to the domestic sale of accounts receivable program described above, the Company's international subsidiaries in Europe and Australia sell accounts receivable to financial institutions without recourse. These arrangements constitute true sales, and once the accounts are sold, they are no longer available to the Company's creditors in the event of bankruptcy. The European program allows the Company’s European subsidiaries to advance up to 90% of eligible receivables sold under the terms of the arrangement. During the first quarter of fiscal 2014, the Company phased out its existing Australian accounts receivable sales program and entered into a new accounts receivable sales program with a different financial institution. Under the new Australian program, accounts receivable balances will be sold to a special purpose vehicle, which in turn will sell 100% of the eligible receivables of Commercial Metals Pty. Ltd., CMC Steel Distribution Pty. Ltd. and G.A.M. Steel Pty. Ltd. to the financial institution. Under the Australian program, the financial institution will fund up to A$75.0 million for all receivables sold, and the remaining portion of the purchase price of the receivables will be paid to the Company from the ultimate collection of the receivables after payment of certain fees and other costs. During the three months ended November 30, 2013, no accounts receivable were sold under the new Australian program. The Company accounts for sales of the receivables as true sales and the trade accounts receivable balances that are sold are removed from the consolidated balance sheets. The cash advances received are reflected as cash provided by operating activities on the Company's consolidated statements of cash flows.
	At November 30, 2013 and August 31, 2013, under its international sale of accounts receivable programs, the Company had sold $55.4 million and $121.2 million of accounts receivable, respectively, to third-party financial institutions and had received advance payments of $31.7 million and $24.5 million, respectively.
	During the three months ended November 30, 2013 and 2012, cash proceeds from the domestic and international sale of accounts receivable programs were $162.8 million and $287.0 million, respectively, and cash payments to the owners of accounts receivable were $159.4 million and $333.6 million, respectively. For a nominal servicing fee, the Company is responsible for servicing the accounts receivable for the domestic and Australian programs. Discounts on domestic and international sales of accounts receivable were $0.6 million and $1.2 million for the three months ended November 30, 2013 and 2012, respectively, and are included in selling, general and administrative expenses in the Company's consolidated statements of operations.
	The deferred purchase price on the Company's domestic and international sale of accounts receivable programs are included in accounts receivable on the Company's consolidated balance sheets. The following tables summarize the activity of the deferred purchase price receivables for the domestic and international sale of accounts receivable programs:
		Three Months Ended November 30, 2013
	(in thousands)	Total			Domestic			Australia			Europe
	Beginning balance	$	453,252		$	358,822		$	64,996		$	29,434
	Transfers of accounts receivable	1,037,205			840,571			73,120			123,514
	Collections	(1,042,922		)	(847,878		)	(65,804		)	(129,240		)
	Program termination	(72,312		)	—			(72,312		)	—
	Ending balance	$	375,223		$	351,515		$	—		$	23,708
		Three Months Ended November 30, 2012
	(in thousands)	Total			Domestic			Australia			Europe
	Beginning balance	$	515,481		$	396,919		$	70,073		$	48,489
	Transfers of accounts receivable	1,206,746			936,630			126,908			143,208
	Collections	(1,186,356		)	(928,556		)	(119,820		)	(137,980		)
	Ending balance	$	535,871		$	404,993		$	77,161		$	53,717

Inventories

Inventories	3 Months Ended
	Nov. 30, 2013
Inventory Disclosure [Abstract]	'
Inventories	'
	NOTE 4. INVENTORIES
	Inventories are stated at the lower of cost or market. Inventory cost for most domestic inventories is determined by the last-in, first-out ("LIFO") method. At November 30, 2013 and August 31, 2013, 39% and 43%, respectively, of the Company's total net inventories were valued at LIFO. LIFO inventory reserves were $189.6 million and $185.5 million at November 30, 2013 and August 31, 2013, respectively. Inventory cost for international inventories and the remaining domestic inventories are determined by the first-in, first-out ("FIFO") method and consisted mainly of material dedicated to CMC Poland Sp. z.o.o. ("CMCP") and certain marketing and distribution businesses.
	The majority of the Company's inventories are in the form of finished goods with minimal work in process. At November 30, 2013 and August 31, 2013, $74.6 million and $66.7 million, respectively, of the Company's inventories were in the form of raw materials.

Goodwill_And_Other_Intangible_

Goodwill And Other Intangible Assets	3 Months Ended
	Nov. 30, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill and other intangible assets	'
	NOTE 5. GOODWILL AND OTHER INTANGIBLE ASSETS
	The following table details the changes in the carrying amount of goodwill by reportable segment:
		Americas						International
	(in thousands)	Recycling		Mills		Fabrication		Mill		Marketing and Distribution		Consolidated
	Balance, August 31, 2013	$	7,267	$	295	$	57,144	$	2,755	$	2,118	$	69,579
	Foreign currency translation	—		—		—		121		33		154
	Balance, November 30, 2013	$	7,267	$	295	$	57,144	$	2,876	$	2,151	$	69,733
	The total gross carrying amounts of the Company's intangible assets that are subject to amortization were $43.3 million and $42.9 million at November 30, 2013 and August 31, 2013, respectively, and are included in other noncurrent assets on the Company's consolidated balance sheets. Excluding goodwill, there are no other significant intangible assets with indefinite lives. Amortization expense for intangible assets was $1.2 million for each of the three months ended November 30, 2013 and 2012.

Businesses_Held_For_Sale_Disco

Businesses Held For Sale, Discontinued Operations And Dispositions	3 Months Ended
	Nov. 30, 2013
Discontinued Operations and Disposal Groups [Abstract]	'
Discontinued operations and dispositions	'
	NOTE 6. BUSINESSES HELD FOR SALE, DISCONTINUED OPERATIONS AND DISPOSITIONS
	Businesses Held for Sale
	The assets and liabilities of businesses classified as held for sale are included in other current assets and accrued expenses on the Company's consolidated balance sheets. The components of assets and liabilities of businesses held for sale are as follows.
	(in thousands)	30-Nov-13		31-Aug-13
	Assets:
	Accounts receivable	$	—	$	20,313
	Inventories, net	—		8,713
	Other current assets	—		3,683
	Property, plant and equipment, net of accumulated depreciation and amortization	1,085		10,459
	Assets of businesses held for sale	$	1,085	$	43,168
	Liabilities:
	Accounts payable-trade	$	—	$	7,615
	Accrued expenses and other payables	—		3,251
	Liabilities of businesses held for sale	$	—	$	10,866
	Discontinued Operations
	During the fourth quarter of fiscal 2013, the Company decided to sell all of the stock of its wholly owned copper tube manufacturing operation, Howell Metal Company ("Howell"). The Company determined that the decision to sell this business met the definition of a discontinued operation. As a result, the Company included Howell in discontinued operations for all periods presented.
	During fiscal 2012, the Company announced its decision to exit the steel pipe manufacturing operations in Croatia ("CMCS") by closure of the facility and sale of the assets. The Company determined that the decision to exit this business met the definition of a discontinued operation. As a result, the Company included CMCS in discontinued operations for all periods presented. The Company sold a majority of CMCS' assets during fiscal 2012. The remaining assets were sold during the first quarter of fiscal 2013 for $3.9 million with no impact to the consolidated statements of operations.
	Financial information for discontinued operations was as follows:
		Three Months Ended November 30,
	(in thousands)	2013		2012
	Net Sales	$	17,298	$	39,711
	Earnings from discontinued operations before income taxes	22,845		1,250
	Dispositions
	On October 17, 2013, the Company sold all of the stock of Howell for $58.5 million, of which $4.2 million is held in escrow, subject to customary purchase price adjustments, resulting in a pre-tax gain of $23.8 million. Howell was previously an operating segment included in the Americas Mills reporting segment.
	During the first quarter of fiscal 2013, the Company completed the sale of its 11% ownership interest in Trinecke Zelezarny, a.s. ("Trinecke"), a Czech Republic joint-stock company, for $29.0 million resulting in a pre-tax gain of $26.1 million. The Trinecke investment was included in the International Marketing and Distribution reporting segment.

Credit_Arrangements

Credit Arrangements	3 Months Ended
	Nov. 30, 2013
Debt Disclosure [Abstract]	'
Credit Arrangements	'
	NOTE 7. CREDIT ARRANGEMENTS
	In May 2013, the Company issued $330.0 million of 4.875% Senior Notes due May 15, 2023 (the "2023 Notes") and received proceeds of $325.0 million, net of underwriting discounts and debt issuance costs. The Company used $205.3 million of the proceeds from the 2023 Notes to purchase all of its outstanding $200.0 million of 5.625% Notes due 2013 (the "2013 Notes"). The Company uses the remaining proceeds for general corporate purposes. Interest on the 2023 Notes is payable semi-annually on May 15 and November 15 of each year, beginning on November 15, 2013. The Company may, at any time, redeem the 2023 Notes at a redemption price equal to 100 percent of the principal amount, plus a "make-whole" premium described in the indenture. Additionally, if a change of control triggering event occurs, as defined by the terms of the indenture, holders of the 2023 Notes may require the Company to repurchase the 2023 Notes at a purchase price equal to 101 percent of the principal amount, plus accrued and unpaid interest, if any, to the date of purchase. The Company is generally not limited under the indenture governing the 2023 Notes in its ability to incur additional indebtedness provided the Company is in compliance with certain restrictive covenants, including restrictions on liens, sale and leaseback transactions, mergers, consolidations and transfers of substantially all of the Company's assets.
	In December 2011, the Company entered into a third amended and restated $300 million revolving credit facility that matures on December 27, 2016. The maximum availability under this facility can be increased to $400 million with the consent of both parties. The program's capacity, with a sublimit of $50 million for letters of credit, is reduced by outstanding stand-by letters of credit which totaled $35.2 million at November 30, 2013. Under the credit facility, the Company was required to maintain a minimum interest coverage ratio (adjusted EBITDA to interest expense, as each is defined in the facility) of not less than 3.00 to 1.00 for the twelve month cumulative period ended November 30, 2012 and for each fiscal quarter on a rolling twelve month cumulative period thereafter. At November 30, 2013, the Company's interest coverage ratio was 4.96 to 1.00. The credit facility also requires the Company to maintain a debt to capitalization ratio that does not exceed 0.60 to 1.00. At November 30, 2013, the Company's debt to capitalization ratio was 0.50 to 1.00. The credit facility provides for interest based on the LIBOR, the Eurodollar rate or Bank of America's prime rate.
	At November 30, 2013, the Company was in compliance with all covenants related to its debt agreements.
	During fiscal 2012, the Company terminated its existing interest rate swap transactions and received cash proceeds of approximately $52.7 million, net of customary finance charges. The resulting gain was deferred and is being amortized as a reduction to interest expense over the remaining term of the respective debt tranches. At November 30, 2013 and August 31, 2013, the unamortized portion was $32.5 million and $34.4 million, respectively, and for the three months ended November 30, 2013 and 2012, the amortization of the deferred gain was $1.9 million and $2.9 million, respectively.
	The Company has uncommitted credit facilities available from domestic and international banks. In general, these credit facilities are used to support trade letters of credit (including accounts payable settled under bankers' acceptances), foreign exchange transactions and short-term advances which are priced at market rates.
	Long-term debt, including the deferred gain from the termination of the interest rate swaps, was as follows:
	(in thousands)	Weighted Average	November 30, 2013		August 31, 2013
		Interest Rate as of November 30, 2013
	$400 million notes at 6.50% due July 2017	5.70%	$	410,775	$	411,518
	$500 million notes at 7.35% due August 2018	6.40%	521,773		522,930
	$330 million notes at 4.875% due May 2023	4.90%	330,000		330,000
	Other, including equipment notes		20,987		19,594
			1,283,535		1,284,042
	Less current maturities		6,232		5,228
			$	1,277,303	$	1,278,814
	Interest on these notes is payable semiannually.
	CMCP has uncommitted credit facilities of $66.3 million with several banks with expiration dates ranging from December 2013 to October 2014. During the three months ended November 30, 2013, CMCP had no borrowings and no repayments under these facilities. At November 30, 2013, no material amounts were outstanding under these facilities.
	The Company had no material amounts of interest capitalized in the cost of property, plant and equipment during the three months ended November 30, 2013 and 2012, respectively. Cash paid for interest during the three months ended November 30, 2013 and 2012 was $9.5 million and $4.6 million, respectively.

Derivatives_And_Risk_Managemen

Derivatives And Risk Management	3 Months Ended
	Nov. 30, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivatives and risk management	'
	NOTE 8. DERIVATIVES AND RISK MANAGEMENT
	The Company's global operations and product lines expose it to risks from fluctuations in metal commodity prices, foreign currency exchange rates, natural gas prices and interest rates. One objective of the Company's risk management program is to mitigate these risks using derivative instruments. The Company enters into metal commodity futures and forward contracts to mitigate the risk of unanticipated changes in gross margin due to the volatility of the commodities' prices, enters into foreign currency forward contracts that match the expected settlements for purchases and sales denominated in foreign currencies and enters into natural gas forward contracts to mitigate the risk of unanticipated changes in operating cost due to the volatility of natural gas prices. When sales commitments to customers include a fixed price freight component, the Company occasionally enters into freight forward contracts to reduce the effects of the volatility of ocean freight rates.
	At November 30, 2013, the notional value of the Company's foreign currency contract commitments and its commodity contract commitments was $433.3 million and $54.9 million, respectively.
	The following table provides information regarding the Company's commodity contract commitments as of November 30, 2013:
	Commodity	Long/Short		Total
	Aluminum	Long		4,945		MT
	Aluminum	Short		1,800		MT
	Copper	Long		476		MT
	Copper	Short		5,443		MT
	Zinc	Long		7		MT
	MT =etric Ton
	The Company designates only those contracts which closely match the terms of the underlying transaction as hedges for accounting purposes. These hedges resulted in substantially no ineffectiveness in the Company's consolidated statements of operations, and there were no components excluded from the assessment of hedge effectiveness for the three months ended November 30, 2013 and 2012. Certain foreign currency and commodity contracts were not designated as hedges for accounting purposes, although management believes they are essential economic hedges.
	The following tables summarize activities related to the Company's derivative instruments and hedged items recognized in the consolidated statements of operations:
				Three Months Ended November 30,
	Derivatives Not Designated as Hedging Instruments (in thousands)	Location		2013				2012
	Commodity	Cost of goods sold		$	510			$	(411	)
	Commodity	SG&A expenses		—				(588		)
	Foreign exchange	Net sales		(159		)		(11		)
	Foreign exchange	Cost of goods sold		(121		)		—
	Foreign exchange	SG&A expenses		(4,693		)		(36		)
	Other	Cost of goods sold		—				15
	Loss before income taxes			$	(4,463	)		$	(1,031	)
	The Company's fair value hedges are designated for accounting purposes with gains and losses on the hedged items offsetting the gain or loss on the related derivative transaction. Hedged items relate to firm commitments on commercial sales and purchases and capital expenditures.
	Derivatives Designated as Fair Value Hedging Instruments (in thousands)			Three Months Ended November 30,
		Location		2013				2012
	Foreign exchange	Net sales		$	(113	)		$	—
	Foreign exchange	Cost of goods sold		(127		)		(229		)
	Loss before income taxes			$	(240	)		$	(229	)
	Hedged Items Designated as Fair Value Hedging Instruments (in thousands)			Three Months Ended November 30,
		Location		2013				2012
	Foreign exchange	Net sales		$	93			$	(23	)
	Foreign exchange	Cost of goods sold		125				157
	Gain before income taxes			$	218			$	134
	Effective Portion of Derivatives Designated as Cash Flow Hedging Instruments Recognized in Accumulated Other Comprehensive Income (Loss) (in thousands)	Three Months Ended November 30,
		2013				2012
	Commodity	$	(89	)		$	14
	Foreign exchange	(1,528		)		303
	Gain (loss), net of income taxes	$	(1,617	)		$	317
	Effective Portion of Derivatives Designated as Cash Flow Hedging Instruments Reclassified from Accumulated Other Comprehensive Income (Loss) (in thousands)			Three Months Ended November 30,
		Location		2013				2012
	Commodity	Cost of  goods sold		$	(89	)		$	—
	Foreign exchange	Net sales		(231		)		51
	Foreign exchange	Cost of goods sold		(758		)		(41		)
	Foreign exchange	SG&A expenses		12				10
	Interest rate	Interest expense		86				102
	Gain (loss), net of income taxes			$	(980	)		$	122
	The Company enters into derivative agreements that include provisions to allow the set-off of certain amounts. Derivative instruments are presented on a gross basis on the Company's consolidated balance sheets. The asset and liability balances in the tables below reflect the gross amounts of derivative instruments at November 30, 2013 and August 31, 2013. The fair value of the Company's derivative instruments on the consolidated balance sheets was as follows:
	Derivative Assets (in thousands)	November 30, 2013				August 31, 2013
	Commodity — not designated for hedge accounting	$	1,357			$	1,066
	Foreign exchange — designated for hedge accounting	1,414				1,626
	Foreign exchange — not designated for hedge accounting	1,971				1,238
	Derivative assets (other current assets and other assets)*	$	4,742			$	3,930
	Derivative Liabilities (in thousands)	November 30, 2013				August 31, 2013
	Commodity — designated for hedge accounting	$	39			$	129
	Commodity — not designated for hedge accounting	1,302				1,268
	Foreign exchange — designated for hedge accounting	889				432
	Foreign exchange — not designated for hedge accounting	1,633				1,738
	Derivative liabilities (accrued expenses, other payables and long-term liabilities)*	$	3,863			$	3,567
	_________________
	* Derivative assets and liabilities do not include the hedged items designated as fair value hedges.
	As of November 30, 2013, all of the Company's derivative instruments designated to hedge exposure to the variability in future cash flows of the forecasted transactions will mature within twelve months.
	All of the instruments are highly liquid and not entered into for trading purposes.

Fair_Value

Fair Value	3 Months Ended
	Nov. 30, 2013
Fair Value Disclosures [Abstract]	'
Fair value	'
	NOTE 9. FAIR VALUE
	The Company has established a fair value hierarchy which prioritizes the inputs to the valuation techniques used to measure fair value into three levels. These levels are determined based on the lowest level input that is significant to the fair value measurement. Levels within the hierarchy are defined as follows:
	Level 1 - Unadjusted quoted prices in active markets for identical assets and liabilities;
	Level 2 - Quoted prices for similar assets and liabilities in active markets (other than those included in Level 1) which are observable, either directly or indirectly; and
	Level 3 - Valuations derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable.
	The following tables summarize information regarding the Company's financial assets and financial liabilities that were measured at fair value on a recurring basis:
						Fair Value Measurements at Reporting Date Using
	(in thousands)	November 30, 2013				Quoted Prices in				Significant  Other				Significant
						Active Markets  for				Observable Inputs				Unobservable  Inputs
						Identical Assets				(Level 2)				(Level 3)
						(Level 1)
	Assets:
	Money market investments (1)	$	371,574			$	371,574			$	—			$	—
	Commodity derivative assets (2)	1,357				1,357				—				—
	Foreign exchange derivative assets (2)	3,385				—				3,385				—
	Liabilities:
	Commodity derivative liabilities (2)	1,341				1,302				39				—
	Foreign exchange derivative liabilities (2)	2,522				—				2,522				—
						Fair Value Measurements at Reporting Date Using
	(in thousands)	August 31, 2013				Quoted Prices in				Significant  Other				Significant
						Active Markets  for				Observable  Inputs				Unobservable  Inputs
						Identical Assets				(Level 2)				(Level 3)
						(Level 1)
	Assets:
	Money market investments (1)	$	236,727			$	236,727			$	—			$	—
	Commodity derivative assets (2)	1,066				1,066				—				—
	Foreign exchange derivative assets (2)	2,864				—				2,864				—
	Liabilities:
	Commodity derivative liabilities (2)	1,397				1,268				129				—
	Foreign exchange derivative liabilities (2)	2,170				—				2,170				—
	_________________
	(1) Money market investments are short-term in nature, and the value is determined by broker quoted prices in active markets. The investment portfolio mix can change each period based on the Company's assessment of investment options.
	(2) Derivative assets and liabilities classified as Level 1 are commodity futures contracts valued based on quoted market prices in the London Metal Exchange or the New York Mercantile Exchange. Amounts in Level 2 are based on broker quotes in the over-the-counter market. Further discussion regarding the Company's use of derivatives and the classification of the assets and liabilities is included in Note 8, Derivatives and Risk Management.
	Fair value of property, plant and equipment held for sale (Level 3) was $3.8 million based on appraised values less costs to sell at November 30, 2013. CMC does not have other assets or intangible assets measured at fair value on a non-recurring basis at November 30, 2013.
	The carrying values of the Company's short-term items, including the deferred purchase prices of accounts receivable, documentary letters of credit and notes payable, approximate fair value due to their short term nature.
	The carrying values and estimated fair values of the Company's financial assets and liabilities that are not required to be measured at fair value on the consolidated balance sheets are as follows:
				November 30, 2013								August 31, 2013
	(in thousands)	Fair Value Hierarchy		Carrying Value				Fair Value				Carrying Value				Fair Value
	$400 million notes at 6.50% due July 2017 (1)	Level 2		$	410,775			$	447,760			$	411,518			$	443,646
	$500 million notes at 7.35% due August 2018 (1)	Level 2		521,773				574,840				522,930				570,429
	$330 million notes at 4.875% due May 2023 (1)	Level 2		330,000				311,025				330,000				298,650
	(1) The fair value of the notes is calculated based on indicated market values.

Income_Tax

Income Tax	3 Months Ended
	Nov. 30, 2013
Income Tax Disclosure [Abstract]	'
Income tax	'
	NOTE 10. INCOME TAX
	The Company's effective income tax rate from continuing operations for the three months ended November 30, 2013 and 2012 was 32.1% and 31.2%, respectively. The Company's effective income tax rate from discontinued operations for the three months ended November 30, 2013 and 2012 was 38.9% and 37.0%, respectively.
	The Company made net payments of $1.4 million and $0.3 million for income taxes during the three months ended November 30, 2013 and 2012, respectively.
	The reserve for unrecognized income tax benefits related to the accounting for uncertainty in income taxes was $28.6 million and $27.4 million, exclusive of interest and penalties, as of November 30, 2013 and 2012, respectively.
	The Company's policy classifies interest recognized on an underpayment of income taxes and any statutory penalties recognized on a tax position as income tax expense and the balances at the end of a reporting period are recorded as part of the current or noncurrent reserve for uncertain income tax positions. For the three months ended November 30, 2013, before any income tax benefits, the Company recorded immaterial amounts of accrued interest and penalties on unrecognized income tax benefits.
	During the twelve months ending November 30, 2014, it is reasonably possible that the statute of limitations may lapse pertaining to positions taken by the Company in prior year income tax returns or that income tax audits in various taxing jurisdictions could be finalized. As a result, the total amount of unrecognized income tax benefits may decrease by approximately $17.9 million, which would reduce the provision for income taxes on earnings by an immaterial amount.
	The Company files income tax returns in the United States and multiple foreign jurisdictions with varying statutes of limitations. In the normal course of business, the Company and its subsidiaries are subject to examination by various taxing authorities. The following is a summary of tax years subject to examination:
	US Federal — 2009 and forward
	US States — 2009 and forward
	Foreign — 2006 and forward
	The Company is currently under examination by the Internal Revenue Service and state revenue authorities from 2009 to 2011. Management believes the Company's recorded tax liabilities as of November 30, 2013 sufficiently reflect the anticipated outcome of these examinations.

Sharebased_Compensation_Plans

Share-based Compensation Plans	3 Months Ended
	Nov. 30, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Share-based compensation plans	'
	NOTE 11. SHARE-BASED COMPENSATION PLANS
	The Company's share-based compensation plans are described, and informational disclosures provided, in Note 15, Share-Based Compensation Plans, to the consolidated financial statements in the Company's Annual Report on Form 10-K for the year ended August 31, 2013. During the three months ended November 30, 2013 and 2012, restricted stock units ("RSUs") and performance stock units ("PSUs") totaling 1.1 million and 1.3 million, respectively, were granted at a weighted-average fair value of $16.75 and $12.99, respectively. Stock appreciation rights ("SARs") were not granted during the three months ended November 30, 2013. The Company granted 0.2 million SARs at a weighted average exercise price of $14.12 during the three months ended November 30, 2012.
	During the three months ended November 30, 2013 and 2012, the Company granted 59,565 equivalent shares of cash-settled RSUs and PSUs and 204,069 equivalent shares of cash-settled RSUs, PSUs and SARs, respectively. The fair value of these cash-settled awards is remeasured each reporting period and is recognized ratably over the service period. As of November 30, 2013, the Company had 2,016,522 equivalent shares in awards outstanding. The Company expects 1,717,684 equivalent shares to vest.
	In general, the RSUs and PSUs granted during fiscal 2014 will vest over a period of three years; however, certain RSUs granted during fiscal 2014 will vest over a period of four years. The RSUs granted during fiscal 2013 will vest over a period of three years. Subject to the achievement of performance targets established by the Compensation Committee of the Board of Directors, the PSUs granted during fiscal 2014 and fiscal 2013 will vest after a period of three years. The SARs granted during fiscal 2013 vest ratably over a period of three years. The SARs have a contractual term of seven years.
	Share-based compensation expense for the three months ended November 30, 2013 and 2012 of $5.5 million and $4.5 million, respectively, is included in selling, general and administrative expenses on the Company's consolidated statements of operations.

Earnings_Per_Share_Attributabl

Earnings Per Share Attributable To CMC	3 Months Ended
	Nov. 30, 2013
Earnings Per Share [Abstract]	'
Earnings per share attributable to CMC	'
	NOTE 12. EARNINGS PER SHARE ATTRIBUTABLE TO CMC
	The calculations of the basic and diluted earnings per share for the three months ended November 30, 2013 and 2012 are as follows:
		Three Months Ended November 30,
	(in thousands, except share data)	2013		2012
	Net earnings attributable to CMC	$	45,919	$	49,717
	Basic earnings per share:
	Shares outstanding for basic earnings per share	117,070,499		116,336,504
	Basic earnings per share attributable to CMC:	$	0.39	$	0.43
	Diluted earnings per share:
	Shares outstanding for basic earnings per share	117,070,499		116,336,504
	Effect of dilutive securities:
	Share-based incentive/purchase plans	1,086,112		757,123
	Shares outstanding for diluted earnings per share	118,156,611		117,093,627
	Diluted earnings per share attributable to CMC:	$	0.39	$	0.42
	Anti-dilutive shares not included above	1,364,036		2,945,188
	All stock options and SARs expire by 2020.
	CMC's restricted stock is included in the number of shares of common stock issued and outstanding, but is omitted from the basic earnings per share calculation until the shares vest.
	The Company did not purchase any shares during the first three months of fiscal 2014 and had remaining authorization to purchase 8,259,647 shares of its common stock at November 30, 2013.

Commitments_And_Contingencies

Commitments And Contingencies	3 Months Ended
	Nov. 30, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Commitments And contingencies	'
	NOTE 13. COMMITMENTS AND CONTINGENCIES
	In the ordinary course of conducting its business, the Company becomes involved in litigation, administrative proceedings and government investigations, including environmental matters. See Note 18, Commitments and Contingencies, to the consolidated financial statements in the Company's Annual Report on Form 10-K for the year ended August 31, 2013.
	On September 18, 2008, the Company was served with a class action antitrust lawsuit alleging violations of Section 1 of the Sherman Act, brought by Standard Iron Works of Scranton, Pennsylvania, against nine steel manufacturing companies, including CMC. The lawsuit, filed in the United States District Court for the Northern District of Illinois, alleges that the defendants conspired to fix, raise, maintain and stabilize the price at which steel products were sold in the United States by artificially restricting the supply of such steel products. The lawsuit, which purports to be brought on behalf of a class consisting of all purchasers of steel products directly from the defendants between January 1, 2005 and September 2008, seeks treble damages and costs, including reasonable attorney fees and pre- and post-judgment interest. Motions for and against class certification have been filed. Oral arguments related to class certification are pending. Discovery on the case merits remains pending. The Company believes the case is without merit and intends to defend it vigorously.
	Since the filing of the direct purchaser lawsuit, a case has been filed in federal court in the Northern District of Illinois on behalf of a class of indirect purchasers in approximately 28 states naming the same defendants and containing allegations substantially identical to those of the Standard Iron Works complaint. That case has in effect been stayed. Another indirect purchaser action was filed in Tennessee state court, again naming the same defendants but contending that the conspiracy continued through 2010. The case has been removed to federal court, and plaintiffs have moved to remand. The motion to remand has not yet been decided, and no motion practice or discovery has taken place. The Company believes that the lawsuits are without merit and plans to defend them vigorously. Due to the uncertainty and the information available at this time, the Company cannot reasonably estimate a range of loss relating to these cases.
	Guarantees
	During fiscal 2012, the Company entered into a guarantee agreement with a bank in connection with a credit facility granted by the bank to a supplier of the Company. The fair value of the guarantee is negligible. The maximum credit facility with the bank was $4.0 million, and the Company's maximum exposure was $2.8 million as of November 30, 2013.

Business_Segments

Business Segments	3 Months Ended
	Nov. 30, 2013
Segment Reporting [Abstract]	'
Business segments	'
	NOTE 14. BUSINESS SEGMENTS
	The Company's reporting segments are based on strategic business areas, which offer different products and services. These segments have different lines of management responsibility as each business requires different marketing strategies and management expertise.
	The Company structures its business into the following five segments: Americas Recycling, Americas Mills, Americas Fabrication, International Mill and International Marketing and Distribution. The Americas Recycling segment processes scrap metals for use as a raw material by manufacturers of new metal products. The Americas Mills segment manufactures finished long steel products including rebar, merchant bar, light structural, some special bar quality (SBQ) and other special sections as well as semi-finished billets for re-rolling and forging applications. The Americas Fabrication segment consists of the Company's rebar and structural fabrication operations, fence post manufacturing plants, construction-related product facilities and plants that heat-treat steel to strengthen and provide flexibility. The International Mill segment includes the Company's minimill and the Company's recycling and fabrication operations in Poland. The International Marketing and Distribution segment includes international operations for the sale, distribution and processing of steel products, ferrous and nonferrous metals and other industrial products. Additionally, this segment includes the Company's U.S.-based marketing and distribution divisions and also operates a recycling facility in Singapore. Corporate contains expenses of the Company's corporate headquarters and interest expense related to its long-term public debt.
	The financial information presented for the International Mill segment excludes CMCS operations. Additionally, the financial information presented for the Americas Mills segment excludes Howell. These operations have been classified as discontinued operations in the consolidated statements of operations. See Note 6, Businesses Held for Sale, Discontinued Operations and Dispositions, for more information.
	The Company uses adjusted operating profit (loss) to measure the financial performance of its segments. Intersegment sales are generally priced at prevailing market prices. Certain corporate administrative expenses are allocated to segments based upon the nature of the expense. The accounting policies of the segments are the same as those described in the summary of significant accounting policies.
	The following is a summary of certain financial information from continuing operations by reportable segment:
		Three Months Ended November 30, 2013
		Americas						International
	(in thousands)	Recycling		Mills		Fabrication		Mill		Marketing and Distribution		Corporate			Eliminations			Continuing Operations
	Net sales-unaffiliated customers	$	293,475	$	291,573	$	353,992	$	228,492	$	509,174	$	6,185		$	—		$	1,682,891
	Intersegment sales	44,727		189,578		4,226		658		1,984		—			(241,173		)	—
	Net sales	338,202		481,151		358,218		229,150		511,158		6,185			(241,173		)	1,682,891
	Adjusted operating profit (loss)	839		65,814		2,217		15,268		503		(18,049		)	597			67,189
	Total assets*	281,102		594,224		608,313		499,366		858,567		1,182,688			(493,199		)	3,531,061
		Three Months Ended November 30, 2012
		Americas						International
	(in thousands)	Recycling		Mills		Fabrication		Mill		Marketing and Distribution		Corporate			Eliminations			Continuing Operations
	Net sales-unaffiliated customers	$	307,471	$	267,105	$	352,747	$	215,858	$	603,535	$	2,799		$	—		$	1,749,515
	Intersegment sales	44,490		189,633		3,845		6,209		5,053		—			(249,230		)	—
	Net sales	351,961		456,738		356,592		222,067		608,588		2,799			(249,230		)	1,749,515
	Adjusted operating profit (loss)	4,494		51,660		10,192		876		40,161		(17,370		)	(660		)	89,353
	Total assets at August 31, 2013*	309,599		598,478		631,510		487,613		838,413		1,075,594			(496,946		)	3,444,261
	* Excludes total assets from discontinued operations of $6.6 million at November 30, 2013 and $50.5 million at August 31, 2013.
	Reconciliations of earnings from continuing operations to adjusted operating profit are provided below:
		Three Months Ended November 30,
	(in thousands)	2013		2012
	Earnings from continuing operations	$	31,961	$	48,931
	Income taxes	15,091		22,189
	Interest expense	19,578		17,024
	Discounts on sales of accounts receivable	559		1,209
	Adjusted operating profit	$	67,189	$	89,353

Accounting_Policies_Policies

Accounting Policies (Policies)	3 Months Ended
	Nov. 30, 2013
Accounting Policies [Abstract]	'
Accounting principles	'
	Accounting Principles
	The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States ("GAAP") on a basis consistent with that used in the Annual Report on Form 10-K filed by Commercial Metals Company ("CMC", and together with its consolidated subsidiaries, the "Company") with the Securities and Exchange Commission ("SEC") for the year ended August 31, 2013, and include all normal recurring adjustments necessary to present fairly the consolidated balance sheets and the consolidated statements of operations, comprehensive income, cash flows and stockholders' equity for the periods indicated. These notes should be read in conjunction with the audited consolidated financial statements and notes included in the Annual Report on Form 10-K for the year ended August 31, 2013. The results of operations for the three month period are not necessarily indicative of the results to be expected for the full year.
Recent accounting pronouncements	'
	Recent Accounting Pronouncements
	In the first quarter of fiscal 2014, the Company adopted guidance issued by the Financial Accounting Standards Board ("FASB") requiring an entity to provide quantitative and qualitative disclosures about the nature of its rights of setoff and related arrangements associated with its financial instruments and derivative instruments. The objective is to make financial statements that are prepared under GAAP more comparable to those prepared under International Financial Reporting Standards. The new disclosures will give financial statement users information about both gross and net exposures. The adoption of this guidance did not have a material impact on the Company's consolidated financial statements.
	In July 2013, the FASB issued guidance requiring entities to net an unrecognized tax benefit with a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward. To the extent a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. The new guidance is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2013. The Company does not expect this guidance to have a material impact on its consolidated financial statements.
	In April 2013, the FASB issued guidance requiring an entity to prepare its financial statements using the liquidation basis of accounting when liquidation is imminent. In addition, the guidance provides principles for the recognition and measurement of assets and liabilities and requirements for financial statements prepared using the liquidation basis of accounting. The new guidance is effective prospectively for entities that determine liquidation is imminent during fiscal years, and interim reporting periods within those years, beginning after December 15, 2013. The Company does not expect this guidance to have a material impact on its consolidated financial statements.
	In March 2013, the FASB issued guidance requiring an entity to release any related cumulative translation adjustment into net income when it either sells a part or all of its investment in a foreign entity or no longer holds a controlling financial interest in a subsidiary or group of assets that is a nonprofit activity or a business within a foreign entity. In addition, the guidance resolves the diversity in practice for the treatment of business combinations achieved in stages involving a foreign entity. The new guidance is effective prospectively for fiscal years, and interim reporting periods within those years, beginning after December 15, 2013. The Company does not expect the adoption of this guidance to have a material impact on its consolidated financial statements.
	In February 2013, the FASB issued guidance requiring an entity to measure obligations resulting from joint and several liability arrangements for which the total amount of the obligation is fixed at the reporting date. The guidance also requires entities to disclose the nature and amount of the obligation as well as other information about the obligation. The new guidance is effective retrospectively for fiscal years, and interim reporting periods within those years, beginning after December 15, 2013. The Company does not expect the adoption of this guidance to have a material impact on its consolidated financial statements.
Fair value measurement	'
	The Company has established a fair value hierarchy which prioritizes the inputs to the valuation techniques used to measure fair value into three levels. These levels are determined based on the lowest level input that is significant to the fair value measurement. Levels within the hierarchy are defined as follows:
	Level 1 - Unadjusted quoted prices in active markets for identical assets and liabilities;
	Level 2 - Quoted prices for similar assets and liabilities in active markets (other than those included in Level 1) which are observable, either directly or indirectly; and
	Level 3 - Valuations derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable.
Income tax uncertainties	'
	The Company's policy classifies interest recognized on an underpayment of income taxes and any statutory penalties recognized on a tax position as income tax expense and the balances at the end of a reporting period are recorded as part of the current or noncurrent reserve for uncertain income tax positions.

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Loss) (Tables)	3 Months Ended
	Nov. 30, 2013
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'
Schedule of accumulated other comprehensive income (loss)	'
	Accumulated other comprehensive income (loss), net of income taxes, is comprised of the following:
	(in thousands)	Foreign Currency Translation				Unrealized Gain (Loss) on Derivatives			Defined Benefit Obligation			Total Accumulated Other Comprehensive Income (Loss)
	Balance, August 31, 2013	$	(27,477	)		$	3,594		$	(3,293	)	$	(27,176	)
	Other comprehensive income (loss) before reclassifications	19,442				(1,617		)	550			18,375
	Amounts reclassified from AOCI	—				980			(2		)	978
	Net other comprehensive income (loss)	19,442				(637		)	548			19,353
	Balance, November 30, 2013	$	(8,035	)		$	2,957		$	(2,745	)	$	(7,823	)
Schedule of reclassification out of accumulated other comprehensive income (loss)	'
	The significant items reclassified out of accumulated other comprehensive income (loss) and the corresponding line items in the consolidated statements of operations to which the items were reclassified were as follows:
	Components of AOCI (in thousands)	Location		Three Months Ended November 30, 2013
	Unrealized gain (loss) on derivatives:
	Commodity	Cost of goods sold		$	(119	)
	Foreign exchange	Net sales		(250		)
	Foreign exchange	Cost of goods sold		(922		)
	Foreign exchange	SG&A expenses		14
	Interest rate	Interest expense		116
				(1,161		)
	Income tax effect	Income taxes (expense) benefit		181
	Net of income taxes			$	(980	)
	Defined benefit obligation:
	Amortization of net gain	SG&A expenses		$	3
	Income tax effect	Income taxes (expense) benefit		(1		)
	Net of income taxes			$	2
	Amounts in parentheses reduce earnings.

Sales_Of_Accounts_Receivable_A

Sales Of Accounts Receivable (Activity of the Deferred Purchase Price Receivables) (Tables)	3 Months Ended
	Nov. 30, 2013
Transfers and Servicing [Abstract]	'
Deferred Purchase Price Receivables [Table Text Block]	'
	The following tables summarize the activity of the deferred purchase price receivables for the domestic and international sale of accounts receivable programs:
		Three Months Ended November 30, 2013
	(in thousands)	Total			Domestic			Australia			Europe
	Beginning balance	$	453,252		$	358,822		$	64,996		$	29,434
	Transfers of accounts receivable	1,037,205			840,571			73,120			123,514
	Collections	(1,042,922		)	(847,878		)	(65,804		)	(129,240		)
	Program termination	(72,312		)	—			(72,312		)	—
	Ending balance	$	375,223		$	351,515		$	—		$	23,708
		Three Months Ended November 30, 2012
	(in thousands)	Total			Domestic			Australia			Europe
	Beginning balance	$	515,481		$	396,919		$	70,073		$	48,489
	Transfers of accounts receivable	1,206,746			936,630			126,908			143,208
	Collections	(1,186,356		)	(928,556		)	(119,820		)	(137,980		)
	Ending balance	$	535,871		$	404,993		$	77,161		$	53,717

Goodwill_And_Other_Intangible_1

Goodwill And Other Intangible Assets (Tables)	3 Months Ended
	Nov. 30, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Changes in the carrying amount of goodwill	'
	The following table details the changes in the carrying amount of goodwill by reportable segment:
		Americas						International
	(in thousands)	Recycling		Mills		Fabrication		Mill		Marketing and Distribution		Consolidated
	Balance, August 31, 2013	$	7,267	$	295	$	57,144	$	2,755	$	2,118	$	69,579
	Foreign currency translation	—		—		—		121		33		154
	Balance, November 30, 2013	$	7,267	$	295	$	57,144	$	2,876	$	2,151	$	69,733

Businesses_Held_For_Sale_Disco1

Businesses Held For Sale, Discontinued Operations And Dispositions (Tables)	3 Months Ended
	Nov. 30, 2013
Discontinued Operations and Disposal Groups [Abstract]	'
Components of assets and liabilities of businesses held for sale	'
	The components of assets and liabilities of businesses held for sale are as follows.
	(in thousands)	30-Nov-13		31-Aug-13
	Assets:
	Accounts receivable	$	—	$	20,313
	Inventories, net	—		8,713
	Other current assets	—		3,683
	Property, plant and equipment, net of accumulated depreciation and amortization	1,085		10,459
	Assets of businesses held for sale	$	1,085	$	43,168
	Liabilities:
	Accounts payable-trade	$	—	$	7,615
	Accrued expenses and other payables	—		3,251
	Liabilities of businesses held for sale	$	—	$	10,866
Financial information for discontinued operations	'
	Financial information for discontinued operations was as follows:
		Three Months Ended November 30,
	(in thousands)	2013		2012
	Net Sales	$	17,298	$	39,711
	Earnings from discontinued operations before income taxes	22,845		1,250

Credit_Arrangements_Tables

Credit Arrangements (Tables)	3 Months Ended
	Nov. 30, 2013
Debt Disclosure [Abstract]	'
Long-term debt, including the deferred gain from the termination of the interest rate swaps	'
	Long-term debt, including the deferred gain from the termination of the interest rate swaps, was as follows:
	(in thousands)	Weighted Average	November 30, 2013		August 31, 2013
		Interest Rate as of November 30, 2013
	$400 million notes at 6.50% due July 2017	5.70%	$	410,775	$	411,518
	$500 million notes at 7.35% due August 2018	6.40%	521,773		522,930
	$330 million notes at 4.875% due May 2023	4.90%	330,000		330,000
	Other, including equipment notes		20,987		19,594
			1,283,535		1,284,042
	Less current maturities		6,232		5,228
			$	1,277,303	$	1,278,814
	Interest on these notes is payable semiannually.

Derivatives_And_Risk_Managemen1

Derivatives And Risk Management (Tables)	3 Months Ended
	Nov. 30, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Commodity contract commitments	'
	The following table provides information regarding the Company's commodity contract commitments as of November 30, 2013:
	Commodity	Long/Short		Total
	Aluminum	Long		4,945		MT
	Aluminum	Short		1,800		MT
	Copper	Long		476		MT
	Copper	Short		5,443		MT
	Zinc	Long		7		MT
	MT =etric Ton
Derivatives not designated as hedging instruments	'
	The following tables summarize activities related to the Company's derivative instruments and hedged items recognized in the consolidated statements of operations:
				Three Months Ended November 30,
	Derivatives Not Designated as Hedging Instruments (in thousands)	Location		2013				2012
	Commodity	Cost of goods sold		$	510			$	(411	)
	Commodity	SG&A expenses		—				(588		)
	Foreign exchange	Net sales		(159		)		(11		)
	Foreign exchange	Cost of goods sold		(121		)		—
	Foreign exchange	SG&A expenses		(4,693		)		(36		)
	Other	Cost of goods sold		—				15
	Loss before income taxes			$	(4,463	)		$	(1,031	)
Derivatives designated as fair value hedging instruments	'
	Hedged items relate to firm commitments on commercial sales and purchases and capital expenditures.
	Derivatives Designated as Fair Value Hedging Instruments (in thousands)			Three Months Ended November 30,
		Location		2013				2012
	Foreign exchange	Net sales		$	(113	)		$	—
	Foreign exchange	Cost of goods sold		(127		)		(229		)
	Loss before income taxes			$	(240	)		$	(229	)
Hedged items designated as fair value hedging instruments	'
	Hedged Items Designated as Fair Value Hedging Instruments (in thousands)			Three Months Ended November 30,
		Location		2013				2012
	Foreign exchange	Net sales		$	93			$	(23	)
	Foreign exchange	Cost of goods sold		125				157
	Gain before income taxes			$	218			$	134
Effective portion of derivatives designated as cash flow hedging instruments recognized In accumulated other comprehensive income (loss)	'
	Effective Portion of Derivatives Designated as Cash Flow Hedging Instruments Recognized in Accumulated Other Comprehensive Income (Loss) (in thousands)	Three Months Ended November 30,
		2013				2012
	Commodity	$	(89	)		$	14
	Foreign exchange	(1,528		)		303
	Gain (loss), net of income taxes	$	(1,617	)		$	317
Effective portion of derivatives designated as cash flow hedging instruments reclassified from accumulated other comprehensive income (loss)	'
	Effective Portion of Derivatives Designated as Cash Flow Hedging Instruments Reclassified from Accumulated Other Comprehensive Income (Loss) (in thousands)			Three Months Ended November 30,
		Location		2013				2012
	Commodity	Cost of  goods sold		$	(89	)		$	—
	Foreign exchange	Net sales		(231		)		51
	Foreign exchange	Cost of goods sold		(758		)		(41		)
	Foreign exchange	SG&A expenses		12				10
	Interest rate	Interest expense		86				102
	Gain (loss), net of income taxes			$	(980	)		$	122
Derivative assets	'
	The fair value of the Company's derivative instruments on the consolidated balance sheets was as follows:
	Derivative Assets (in thousands)	November 30, 2013				August 31, 2013
	Commodity — not designated for hedge accounting	$	1,357			$	1,066
	Foreign exchange — designated for hedge accounting	1,414				1,626
	Foreign exchange — not designated for hedge accounting	1,971				1,238
	Derivative assets (other current assets and other assets)*	$	4,742			$	3,930
Derivative liabilities	'
	Derivative Liabilities (in thousands)	November 30, 2013				August 31, 2013
	Commodity — designated for hedge accounting	$	39			$	129
	Commodity — not designated for hedge accounting	1,302				1,268
	Foreign exchange — designated for hedge accounting	889				432
	Foreign exchange — not designated for hedge accounting	1,633				1,738
	Derivative liabilities (accrued expenses, other payables and long-term liabilities)*	$	3,863			$	3,567
	_________________
	* Derivative assets and liabilities do not include the hedged items designated as fair value hedges.

Fair_Value_Tables

Fair Value (Tables)	3 Months Ended
	Nov. 30, 2013
Fair Value Disclosures [Abstract]	'
Financial assets and financial liabilities measured at fair value on a recurring basis	'
	The following tables summarize information regarding the Company's financial assets and financial liabilities that were measured at fair value on a recurring basis:
						Fair Value Measurements at Reporting Date Using
	(in thousands)	November 30, 2013				Quoted Prices in				Significant  Other				Significant
						Active Markets  for				Observable Inputs				Unobservable  Inputs
						Identical Assets				(Level 2)				(Level 3)
						(Level 1)
	Assets:
	Money market investments (1)	$	371,574			$	371,574			$	—			$	—
	Commodity derivative assets (2)	1,357				1,357				—				—
	Foreign exchange derivative assets (2)	3,385				—				3,385				—
	Liabilities:
	Commodity derivative liabilities (2)	1,341				1,302				39				—
	Foreign exchange derivative liabilities (2)	2,522				—				2,522				—
						Fair Value Measurements at Reporting Date Using
	(in thousands)	August 31, 2013				Quoted Prices in				Significant  Other				Significant
						Active Markets  for				Observable  Inputs				Unobservable  Inputs
						Identical Assets				(Level 2)				(Level 3)
						(Level 1)
	Assets:
	Money market investments (1)	$	236,727			$	236,727			$	—			$	—
	Commodity derivative assets (2)	1,066				1,066				—				—
	Foreign exchange derivative assets (2)	2,864				—				2,864				—
	Liabilities:
	Commodity derivative liabilities (2)	1,397				1,268				129				—
	Foreign exchange derivative liabilities (2)	2,170				—				2,170				—
	_________________
	(1) Money market investments are short-term in nature, and the value is determined by broker quoted prices in active markets. The investment portfolio mix can change each period based on the Company's assessment of investment options.
	(2) Derivative assets and liabilities classified as Level 1 are commodity futures contracts valued based on quoted market prices in the London Metal Exchange or the New York Mercantile Exchange. Amounts in Level 2 are based on broker quotes in the over-the-counter market. Further discussion regarding the Company's use of derivatives and the classification of the assets and liabilities is included in Note 8, Derivatives and Risk Management.
Financial assets and liabilities not required to be measured at fair value	'
	The carrying values and estimated fair values of the Company's financial assets and liabilities that are not required to be measured at fair value on the consolidated balance sheets are as follows:
				November 30, 2013								August 31, 2013
	(in thousands)	Fair Value Hierarchy		Carrying Value				Fair Value				Carrying Value				Fair Value
	$400 million notes at 6.50% due July 2017 (1)	Level 2		$	410,775			$	447,760			$	411,518			$	443,646
	$500 million notes at 7.35% due August 2018 (1)	Level 2		521,773				574,840				522,930				570,429
	$330 million notes at 4.875% due May 2023 (1)	Level 2		330,000				311,025				330,000				298,650
	(1) The fair value of the notes is calculated based on indicated market values.

Earnings_Per_Share_Attributabl1

Earnings Per Share Attributable To CMC (Tables)	3 Months Ended
	Nov. 30, 2013
Earnings Per Share [Abstract]	'
Calculations of the basic and diluted earnings per share	'
	The calculations of the basic and diluted earnings per share for the three months ended November 30, 2013 and 2012 are as follows:
		Three Months Ended November 30,
	(in thousands, except share data)	2013		2012
	Net earnings attributable to CMC	$	45,919	$	49,717
	Basic earnings per share:
	Shares outstanding for basic earnings per share	117,070,499		116,336,504
	Basic earnings per share attributable to CMC:	$	0.39	$	0.43
	Diluted earnings per share:
	Shares outstanding for basic earnings per share	117,070,499		116,336,504
	Effect of dilutive securities:
	Share-based incentive/purchase plans	1,086,112		757,123
	Shares outstanding for diluted earnings per share	118,156,611		117,093,627
	Diluted earnings per share attributable to CMC:	$	0.39	$	0.42
	Anti-dilutive shares not included above	1,364,036		2,945,188

Business_Segments_Tables

Business Segments (Tables)	3 Months Ended
	Nov. 30, 2013
Segment Reporting [Abstract]	'
Summary of certain financial information from continuing operations by reportable segment	'
	The following is a summary of certain financial information from continuing operations by reportable segment:
		Three Months Ended November 30, 2013
		Americas						International
	(in thousands)	Recycling		Mills		Fabrication		Mill		Marketing and Distribution		Corporate			Eliminations			Continuing Operations
	Net sales-unaffiliated customers	$	293,475	$	291,573	$	353,992	$	228,492	$	509,174	$	6,185		$	—		$	1,682,891
	Intersegment sales	44,727		189,578		4,226		658		1,984		—			(241,173		)	—
	Net sales	338,202		481,151		358,218		229,150		511,158		6,185			(241,173		)	1,682,891
	Adjusted operating profit (loss)	839		65,814		2,217		15,268		503		(18,049		)	597			67,189
	Total assets*	281,102		594,224		608,313		499,366		858,567		1,182,688			(493,199		)	3,531,061
		Three Months Ended November 30, 2012
		Americas						International
	(in thousands)	Recycling		Mills		Fabrication		Mill		Marketing and Distribution		Corporate			Eliminations			Continuing Operations
	Net sales-unaffiliated customers	$	307,471	$	267,105	$	352,747	$	215,858	$	603,535	$	2,799		$	—		$	1,749,515
	Intersegment sales	44,490		189,633		3,845		6,209		5,053		—			(249,230		)	—
	Net sales	351,961		456,738		356,592		222,067		608,588		2,799			(249,230		)	1,749,515
	Adjusted operating profit (loss)	4,494		51,660		10,192		876		40,161		(17,370		)	(660		)	89,353
	Total assets at August 31, 2013*	309,599		598,478		631,510		487,613		838,413		1,075,594			(496,946		)	3,444,261
	* Excludes total assets from discontinued operations of $6.6 million at November 30, 2013 and $50.5 million at August 31, 2013.
Reconciliations of earnings from continuing operations to adjusted operating profit	'
	Reconciliations of earnings from continuing operations to adjusted operating profit are provided below:
		Three Months Ended November 30,
	(in thousands)	2013		2012
	Earnings from continuing operations	$	31,961	$	48,931
	Income taxes	15,091		22,189
	Interest expense	19,578		17,024
	Discounts on sales of accounts receivable	559		1,209
	Adjusted operating profit	$	67,189	$	89,353

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income (Loss) (AOCI by Components) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Balance, August 31, 2013	($27,176)	'
Other comprehensive income (loss) before reclassifications	18,375	'
Amounts reclassified from AOCI	978	'
Net other comprehensive income (loss)	19,353	23,412
Balance, November 30, 2013	-7,823	'
Foreign Currency Translation	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Balance, August 31, 2013	-27,477	'
Other comprehensive income (loss) before reclassifications	19,442	'
Amounts reclassified from AOCI	0	'
Net other comprehensive income (loss)	19,442	'
Balance, November 30, 2013	-8,035	'
Unrealized Gain (Loss) on Derivatives	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Balance, August 31, 2013	3,594	'
Other comprehensive income (loss) before reclassifications	-1,617	'
Amounts reclassified from AOCI	980	'
Net other comprehensive income (loss)	-637	'
Balance, November 30, 2013	2,957	'
Defined Benefit Plans Adjustment	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Balance, August 31, 2013	-3,293	'
Other comprehensive income (loss) before reclassifications	550	'
Amounts reclassified from AOCI	-2	'
Net other comprehensive income (loss)	548	'
Balance, November 30, 2013	($2,745)	'

Accumulated_Other_Comprehensiv3

Accumulated Other Comprehensive Income (Loss) (Reclassification from AOCI) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Unrealized gain (loss) on derivatives:	'	'
Income taxes (expense) benefit	$181	($49)
Net of income taxes	-980	122
Unrealized gain (loss) on derivatives	'	'
Unrealized gain (loss) on derivatives:	'	'
Reclassification adjustments from AOCI on derivatives, before tax	-1,161	'
Income taxes (expense) benefit	181	'
Net of income taxes	-980	'
Unrealized gain (loss) on derivatives | Commodity | Cost of goods sold	'	'
Unrealized gain (loss) on derivatives:	'	'
Reclassification adjustments from AOCI on derivatives, before tax	-119	'
Unrealized gain (loss) on derivatives | Foreign exchange | Cost of goods sold	'	'
Unrealized gain (loss) on derivatives:	'	'
Reclassification adjustments from AOCI on derivatives, before tax	-922	'
Unrealized gain (loss) on derivatives | Foreign exchange | Net sales	'	'
Unrealized gain (loss) on derivatives:	'	'
Reclassification adjustments from AOCI on derivatives, before tax	-250	'
Unrealized gain (loss) on derivatives | Foreign exchange | SG&A expenses	'	'
Unrealized gain (loss) on derivatives:	'	'
Reclassification adjustments from AOCI on derivatives, before tax	14	'
Unrealized gain (loss) on derivatives | Interest rate | Interest expense	'	'
Unrealized gain (loss) on derivatives:	'	'
Reclassification adjustments from AOCI on derivatives, before tax	116	'
Defined benefit obligation	'	'
Defined benefit obligation:	'	'
Income taxes (expense) benefit	-1	'
Net of Income taxes	2	'
Defined benefit obligation | SG&A expenses	'	'
Defined benefit obligation:	'	'
Amortization of net gain	$3	'

Sales_Of_Accounts_Receivable_N

Sales Of Accounts Receivable (Narrative) (Details)	3 Months Ended						3 Months Ended
	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Aug. 31, 2013	Nov. 30, 2013	Aug. 31, 2013	Nov. 30, 2013	Nov. 30, 2013	Nov. 30, 2013
	USD ($)	USD ($)	Domestic [Member]	Domestic [Member]	International [Member]	International [Member]	Europe [Member]	Australia [Member]	Australia [Member]
			USD ($)	USD ($)	USD ($)	USD ($)		AUD	USD ($)
			entities
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]	'	'	'	'	'	'	'	'	'
Number of financial institutions	'	'	2	'	'	'	'	'	'
Advances, maximum percentage of eligible receivables	'	'	'	'	'	'	90.00%	'	'
Percentage of eligible receivables sold	'	'	'	'	'	'	'	100.00%	'
Sale of receivables maximum facility	'	'	$200,000,000	'	'	'	'	75,000,000	'
Accounts receivable sold	'	'	356,900,000	358,800,000	55,400,000	121,200,000	'	'	0
Advance payment received on sale of account receivable	'	'	0	0	31,700,000	24,500,000	'	'	'
Cash proceeds	162,800,000	287,000,000	'	'	'	'	'	'	'
Cash payments	159,400,000	333,600,000	'	'	'	'	'	'	'
Discounts on sales of accounts receivable	$559,000	$1,209,000	'	'	'	'	'	'	'

Sales_Of_Accounts_Receivable_A1

Sales Of Accounts Receivable (Activity of Deferred Purchase Price Receivables) (Details) (USD $)	Nov. 30, 2013	Aug. 31, 2013	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012
In Thousands, unless otherwise specified			Deferred Purchase Price Receivables [Member]	Deferred Purchase Price Receivables [Member]	Domestic [Member]	Domestic [Member]	Australia [Member]	Australia [Member]	Europe [Member]	Europe [Member]
					Deferred Purchase Price Receivables [Member]	Deferred Purchase Price Receivables [Member]	Deferred Purchase Price Receivables [Member]	Deferred Purchase Price Receivables [Member]	Deferred Purchase Price Receivables [Member]	Deferred Purchase Price Receivables [Member]
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]	'	'	'	'	'	'	'	'	'	'
Beginning balance	$927,100	$989,694	$453,252	$515,481	$358,822	$396,919	$64,996	$70,073	$29,434	$48,489
Transfers of accounts receivable	'	'	1,037,205	1,206,746	840,571	936,630	73,120	126,908	123,514	143,208
Collections	'	'	-1,042,922	-1,186,356	-847,878	-928,556	-65,804	-119,820	-129,240	-137,980
Program termination	'	'	-72,312	'	0	'	-72,312	'	0	'
Ending balance	$927,100	$989,694	$375,223	$535,871	$351,515	$404,993	$0	$77,161	$23,708	$53,717

Inventories_Narrative_Details

Inventories (Narrative) (Details) (USD $)	Nov. 30, 2013	Aug. 31, 2013
In Millions, unless otherwise specified
Inventory Disclosure [Abstract]	'	'
Inventory, LIFO reserve	$189.60	$185.50
Percentage of total inventory valued at LIFO	39.00%	43.00%
Raw materials	$74.60	$66.70

Goodwill_And_Other_Intangible_2

Goodwill And Other Intangible Assets (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012	Aug. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'	'	'
Gross carrying amounts of the Company's intangible assets	$43.30	'	$42.90
Amortization expense for intangible assets	$1.20	$1.20	'

Goodwill_And_Other_Intangible_3

Goodwill And Other Intangible Assets (Changes in the Carrying Amount of Goodwill) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013
Goodwill [Roll Forward]	'
Balance, August 31, 2013	$69,579
Foreign currency translation	154
Balance, November 30, 2013	69,733
Americas Recycling [Member]	'
Goodwill [Roll Forward]	'
Balance, August 31, 2013	7,267
Foreign currency translation	0
Balance, November 30, 2013	7,267
Americas Mills [Member]	'
Goodwill [Roll Forward]	'
Balance, August 31, 2013	295
Foreign currency translation	0
Balance, November 30, 2013	295
Americas Fabrication [Member]	'
Goodwill [Roll Forward]	'
Balance, August 31, 2013	57,144
Foreign currency translation	0
Balance, November 30, 2013	57,144
International Mill [Member]	'
Goodwill [Roll Forward]	'
Balance, August 31, 2013	2,755
Foreign currency translation	121
Balance, November 30, 2013	2,876
International Marketing and Distribution [Member]	'
Goodwill [Roll Forward]	'
Balance, August 31, 2013	2,118
Foreign currency translation	33
Balance, November 30, 2013	$2,151

Businesses_Held_For_Sale_Disco2

Businesses Held For Sale, Discontinued Operations And Dispositions (Narrative) (Details) (USD $)	3 Months Ended			0 Months Ended	3 Months Ended
	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2012	Oct. 17, 2013	Nov. 30, 2013	Nov. 30, 2012
			CMCS [Member]	Howell [Member]	Howell [Member]	Trinecke Zelezarny [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'	'	'	'	'
Business divestiture disposal price	'	'	$3,900,000	$58,500,000	'	$29,000,000
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax	'	'	'	'	23,800,000	'
Escrow receivable	'	'	'	4,200,000	'	'
Sale of Stock, Percentage of Ownership before Transaction	'	'	'	'	'	11.00%
Cost-method investments, pre-tax gains	$0	$26,088,000	'	'	'	$26,100,000

Businesses_Held_For_Sale_Disco3

Businesses Held For Sale, Discontinued Operations And Dispositions (Components Of Assets And Liabilities Of Businesses Held For Sale) (Details) (USD $)	Nov. 30, 2013	Aug. 31, 2013
In Thousands, unless otherwise specified
Assets:	'	'
Accounts receivable	$0	$20,313
Inventories, net	0	8,713
Other current assets	0	3,683
Property, plant and equipment, net of accumulated depreciation and amortization	1,085	10,459
Assets of businesses held for sale	1,085	43,168
Liabilities:	'	'
Accounts payable-trade	0	7,615
Accrued expenses and other payables	0	3,251
Liabilities of businesses held for sale	$0	$10,866

Businesses_Held_For_Sale_Disco4

Businesses Held For Sale, Discontinued Operations And Dispositions (Financial Information for Discontinued Operations) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'
Earnings from discontinued operations before income taxes	$22,845	$1,250
Segment, Discontinued Operations [Member]	'	'
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'
Net Sales	17,298	39,711
Earnings from discontinued operations before income taxes	$22,845	$1,250

Credit_Arrangements_Narrative_

Credit Arrangements (Narrative) (Details) (USD $)

3 Months Ended

12 Months Ended

3 Months Ended

1 Months Ended

12 Months Ended

Nov. 30, 2013

Nov. 30, 2012

Aug. 31, 2012

Aug. 31, 2013

Nov. 30, 2013

Nov. 30, 2013

Nov. 30, 2013

31-May-13

Aug. 31, 2013

Nov. 30, 2013

Nov. 30, 2013

31-May-13

CMCP [Member]

Revolving Credit Facility [Member]

Letter of Credit [Member]

$330 million notes at 4.875% due May 2023 [Member]

$330 million notes at 4.875% due May 2023 [Member]

$330 million notes at 4.875% due May 2023 [Member]

Change of control triggering event

$200 million notes at 5.625% due November 2013 [Member]

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Debt instrument, face amount

'

'

'

'

'

'

'

$330,000,000

$330,000,000

$330,000,000

'

$200,000,000

Debt instrument, interest rate, stated percentage

'

'

'

'

'

'

'

4.88%

4.88%

4.88%

'

'

Debt instrument, maturity date

'

'

'

'

'

'

'

15-May-23

'

'

'

'

Proceeds from issuance of debt, net of underwriting discounts and debt issuance costs

'

'

'

'

'

'

'

325,000,000

'

'

'

'

Debt extinguishment total cash outflow

'

'

'

'

'

'

'

'

205.3

'

'

'

Redemption purchase price to principal amount, percentage

'

'

'

'

'

'

'

'

'

100.00%

101.00%

'

Repayments of Long-term debt

1,551,000

1,284,000

'

'

'

'

'

'

'

'

'

'

Line of credit facility, current borrowing capacity

'

'

'

'

66,300,000

300,000,000

50,000,000

'

'

'

'

'

Revolving credit facility, maturity date

'

'

'

'

'

27-Dec-16

'

'

'

'

'

'

Revolving credit facility, maximum borrowing capacity

'

'

'

'

'

400,000,000

'

'

'

'

'

'

Stand by letters of credit outstanding amount

'

'

'

'

'

'

35,200,000

'

'

'

'

'

Minimum interest coverage ratio

'

'

'

'

'

300.00%

'

'

'

'

'

'

Actual interest coverage ratio

'

'

'

'

'

496.00%

'

'

'

'

'

'

Maximum debt to capitalization ratio

'

'

'

'

'

60.00%

'

'

'

'

'

'

Actual debt to capitalization ratio

'

'

'

'

'

50.00%

'

'

'

'

'

'

Net Proceeds From Termination Of Interest Rate Swaps

'

'

52,700,000

'

'

'

'

'

'

'

'

'

Unamortized deferred gain on termination of interest rate swaps

32,500,000

'

'

34,400,000

'

'

'

'

'

'

'

'

Amortization of interest rate swaps termination gain

1,900,000

2,908,000

'

'

'

'

'

'

'

'

'

'

Period total borrowing

'

'

'

'

0

'

'

'

'

'

'

'

Period total payments

'

'

'

'

0

'

'

'

'

'

'

'

Interest paid

$9,500,000

$4,600,000

'

'

'

'

'

'

'

'

'

'

Credit_Arrangements_Longterm_D

Credit Arrangements (Long-term Debt, Including the Deferred Gain from the Termination of the Interest Rate Swaps) (Details) (USD $)	3 Months Ended	12 Months Ended
	Nov. 30, 2013	Aug. 31, 2013	31-May-13
Debt Instrument [Line Items]	'	'	'
Total long-term debt including current maturities	$1,283,535,000	$1,284,042,000	'
Current maturities of long-term debt	6,232,000	5,228,000	'
Long-term debt	1,277,303,000	1,278,814,000	'
$400 million notes at 6.50% due July 2017 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Debt instrument, face amount	400,000,000	400,000,000	'
Debt instrument, interest rate, stated percentage	6.50%	6.50%	'
Debt instrument, maturity date	'July 2017	'July 2017	'
Weighted average interest rate	5.70%	'	'
Total long-term debt including current maturities	410,775,000	411,518,000	'
$500 million notes at 7.35% due August 2018 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Debt instrument, face amount	500,000,000	500,000,000	'
Debt instrument, interest rate, stated percentage	7.35%	7.35%	'
Debt instrument, maturity date	'August 2018	'August 2018	'
Weighted average interest rate	6.40%	'	'
Total long-term debt including current maturities	521,773,000	522,930,000	'
$330 million notes at 4.875% due May 2023 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Debt instrument, face amount	330,000,000	330,000,000	330,000,000
Debt instrument, interest rate, stated percentage	4.88%	4.88%	4.88%
Debt instrument, maturity date	'May 15, 2023	'May 15, 2023	'
Weighted average interest rate	4.90%	'	'
Total long-term debt including current maturities	330,000,000	330,000,000	'
Other, including equipment notes [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Total long-term debt including current maturities	$20,987,000	$19,594,000	'

Derivatives_And_Risk_Managemen2

Derivatives And Risk Management (Narrative) (Details) (USD $)	Nov. 30, 2013
In Millions, unless otherwise specified
Foreign exchange [Member]	'
Derivative [Line Items]	'
Derivative, Notional Amount	$433.30
Commodity [Member]	'
Derivative [Line Items]	'
Derivative, Notional Amount	$54.90

Derivatives_And_Risk_Managemen3

Derivatives And Risk Management (Commodity Contract Commitments) (Details)	Nov. 30, 2013
	t
Aluminum [Member] | Long [Member]	'
Derivative [Line Items]	'
Commodity Contract Commitments	4,945
Aluminum [Member] | Short [Member]	'
Derivative [Line Items]	'
Commodity Contract Commitments	1,800
Copper [Member] | Long [Member]	'
Derivative [Line Items]	'
Commodity Contract Commitments	476
Copper [Member] | Short [Member]	'
Derivative [Line Items]	'
Commodity Contract Commitments	5,443
Zinc [Member] | Long [Member]	'
Derivative [Line Items]	'
Commodity Contract Commitments	7

Derivatives_And_Risk_Managemen4

Derivatives And Risk Management (Derivatives Not Designated As Hedging Instruments) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for derivatives not designated as hedges	($4,463)	($1,031)
Commodity [Member] | Cost of goods sold	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for derivatives not designated as hedges	510	-411
Commodity [Member] | SG&A expenses [Member]	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for derivatives not designated as hedges	0	-588
Foreign exchange [Member] | Net sales	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for derivatives not designated as hedges	-159	-11
Foreign exchange [Member] | Cost of goods sold	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for derivatives not designated as hedges	-121	0
Foreign exchange [Member] | SG&A expenses [Member]	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for derivatives not designated as hedges	-4,693	-36
Other [Member] | Cost of goods sold	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for derivatives not designated as hedges	$0	$15

Derivatives_And_Risk_Managemen5

Derivatives And Risk Management (Derivatives Designated As Fair Value Hedging Instruments) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for fair value hedges	($240)	($229)
Foreign exchange [Member] | Net sales	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for fair value hedges	-113	0
Foreign exchange [Member] | Cost of goods sold	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for fair value hedges	($127)	($229)

Derivatives_And_Risk_Managemen6

Derivatives And Risk Management (Hedged Items Designated As Fair Value Hedging Instruments) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for hedged items of fair value hedges	$218	$134
Foreign exchange [Member] | Net sales	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for hedged items of fair value hedges	93	-23
Foreign exchange [Member] | Cost of goods sold	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss) before income taxes for hedged items of fair value hedges	$125	$157

Derivatives_And_Risk_Managemen7

Derivatives And Risk Management (Effective Portion Of Derivatives Designated As Cash Flow Hedging Instruments Recognized In Accumulated Other Comprehensive Income (Loss)) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss), net of income taxes, for cash flow hedges recognized in AOCI	($1,617)	$317
Commodity [Member]	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss), net of income taxes, for cash flow hedges recognized in AOCI	-89	14
Foreign exchange [Member]	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss), net of income taxes, for cash flow hedges recognized in AOCI	($1,528)	$303

Derivatives_And_Risk_Managemen8

Derivatives And Risk Management (Effective Portion of Derivatives Designated as Cash Flow Hedging Instruments Reclassified from Accumulated Other Comprehensive Income (Loss)) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss), net of income taxes, for cash flow hedges reclassified from AOCI	($980)	$122
Commodity [Member] | Cost of goods sold	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss), net of income taxes, for cash flow hedges reclassified from AOCI	-89	0
Foreign exchange [Member] | Net sales	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss), net of income taxes, for cash flow hedges reclassified from AOCI	-231	51
Foreign exchange [Member] | Cost of goods sold	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss), net of income taxes, for cash flow hedges reclassified from AOCI	-758	-41
Foreign exchange [Member] | SG&A expenses [Member]	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss), net of income taxes, for cash flow hedges reclassified from AOCI	12	10
Interest rate | Interest expense	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Gain (loss), net of income taxes, for cash flow hedges reclassified from AOCI	$86	$102

Derivatives_And_Risk_Managemen9

Derivatives And Risk Management (Derivative Assets) (Details) (USD $)	Nov. 30, 2013		Aug. 31, 2013
In Thousands, unless otherwise specified
Derivatives, Fair Value [Line Items]	'		'
Derivative assets (other current assets and other assets)	$4,742	[1]	$3,930	[1]
Commodity [Member] | Not designated for hedge accounting [Member]	'		'
Derivatives, Fair Value [Line Items]	'		'
Derivative assets (other current assets and other assets)	1,357		1,066
Foreign exchange [Member] | Designated for hedge accounting [Member]	'		'
Derivatives, Fair Value [Line Items]	'		'
Derivative assets (other current assets and other assets)	1,414		1,626
Foreign exchange [Member] | Not designated for hedge accounting [Member]	'		'
Derivatives, Fair Value [Line Items]	'		'
Derivative assets (other current assets and other assets)	$1,971		$1,238
[1]	* Derivative assets and liabilities do not include the hedged items designated as fair value hedges.

Recovered_Sheet1

Derivatives And Risk Management (Derivative Liabilities) (Details) (USD $)	Nov. 30, 2013		Aug. 31, 2013
In Thousands, unless otherwise specified
Derivatives, Fair Value [Line Items]	'		'
Derivative liabilities (accrued expenses, other payables and long-term liabilities)	$3,863	[1]	$3,567	[1]
Commodity [Member] | Designated for hedge accounting [Member]	'		'
Derivatives, Fair Value [Line Items]	'		'
Derivative liabilities (accrued expenses, other payables and long-term liabilities)	39		129
Commodity [Member] | Not designated for hedge accounting [Member]	'		'
Derivatives, Fair Value [Line Items]	'		'
Derivative liabilities (accrued expenses, other payables and long-term liabilities)	1,302		1,268
Foreign exchange [Member] | Designated for hedge accounting [Member]	'		'
Derivatives, Fair Value [Line Items]	'		'
Derivative liabilities (accrued expenses, other payables and long-term liabilities)	889		432
Foreign exchange [Member] | Not designated for hedge accounting [Member]	'		'
Derivatives, Fair Value [Line Items]	'		'
Derivative liabilities (accrued expenses, other payables and long-term liabilities)	$1,633		$1,738
[1]	* Derivative assets and liabilities do not include the hedged items designated as fair value hedges.

Fair_Value_Narrative_Details

Fair Value (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013
	levels
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'
Number of fair value hierarchy	3
Fair value, inputs, level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member]	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'
Plant, property and equipment	3.8

Fair_Value_Financial_Assets_an

Fair Value (Financial Assets and Financial Liabilities Measured at Fair Value on Recurring Basis) (Details) (USD $)	Nov. 30, 2013		Aug. 31, 2013
In Thousands, unless otherwise specified
Money market investments [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Assets, Fair Value Disclosure, Recurring	$371,574	[1]	$236,727	[1]
Commodity derivatives [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Assets, Fair Value Disclosure, Recurring	1,357	[2]	1,066	[2]
Liabilities, Fair Value Disclosure, Recurring	1,341	[2]	1,397	[2]
Foreign exchange derivatives [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Assets, Fair Value Disclosure, Recurring	3,385	[2]	2,864	[2]
Liabilities, Fair Value Disclosure, Recurring	2,522	[2]	2,170	[2]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Money market investments [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Assets, Fair Value Disclosure, Recurring	371,574	[1]	236,727	[1]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Commodity derivatives [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Assets, Fair Value Disclosure, Recurring	1,357	[2]	1,066	[2]
Liabilities, Fair Value Disclosure, Recurring	1,302	[2]	1,268	[2]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Foreign exchange derivatives [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Assets, Fair Value Disclosure, Recurring	0	[2]	0	[2]
Liabilities, Fair Value Disclosure, Recurring	0	[2]	0	[2]
Significant Other Observable Inputs (Level 2) [Member] | Money market investments [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Assets, Fair Value Disclosure, Recurring	0	[1]	0	[1]
Significant Other Observable Inputs (Level 2) [Member] | Commodity derivatives [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Assets, Fair Value Disclosure, Recurring	0	[2]	0	[2]
Liabilities, Fair Value Disclosure, Recurring	39	[2]	129	[2]
Significant Other Observable Inputs (Level 2) [Member] | Foreign exchange derivatives [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Assets, Fair Value Disclosure, Recurring	3,385	[2]	2,864	[2]
Liabilities, Fair Value Disclosure, Recurring	2,522	[2]	2,170	[2]
Significant Unobservable Inputs (Level 3) [Member] | Money market investments [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Assets, Fair Value Disclosure, Recurring	0	[1]	0	[1]
Significant Unobservable Inputs (Level 3) [Member] | Commodity derivatives [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Assets, Fair Value Disclosure, Recurring	0	[2]	0	[2]
Liabilities, Fair Value Disclosure, Recurring	0	[2]	0	[2]
Significant Unobservable Inputs (Level 3) [Member] | Foreign exchange derivatives [Member]	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Assets, Fair Value Disclosure, Recurring	0	[2]	0	[2]
Liabilities, Fair Value Disclosure, Recurring	$0	[2]	$0	[2]
[1]	Money market investments are short-term in nature, and the value is determined by broker quoted prices in active markets. The investment portfolio mix can change each period based on the Company's assessment of investment options.
[2]	Derivative assets and liabilities classified as Level 1 are commodity futures contracts valued based on quoted market prices in the London Metal Exchange or the New York Mercantile Exchange. Amounts in Level 2 are based on broker quotes in the over-the-counter market. Further discussion regarding the Company's use of derivatives and the classification of the assets and liabilities is included in Note 8, Derivatives and Risk Management.

Fair_Value_Financial_Assets_an1

Fair Value (Financial Assets and Liabilities Not Required to Be Measured at Fair Value) (Details) (USD $)	Nov. 30, 2013		Aug. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Debt and Capital Lease Obligations	$1,283,535		$1,284,042
$400 million notes at 6.50% due July 2017 [Member]	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Debt and Capital Lease Obligations	410,775		411,518
$400 million notes at 6.50% due July 2017 [Member] | Level 2 [Member] | Carrying Value [Member]	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Debt and Capital Lease Obligations	410,775		411,518
$400 million notes at 6.50% due July 2017 [Member] | Level 2 [Member] | Fair Value [Member]	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Debt and Capital Lease Obligations	447,760	[1]	443,646	[1]
$500 million notes at 7.35% due August 2018 [Member]	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Debt and Capital Lease Obligations	521,773		522,930
$500 million notes at 7.35% due August 2018 [Member] | Level 2 [Member] | Carrying Value [Member]	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Debt and Capital Lease Obligations	521,773		522,930
$500 million notes at 7.35% due August 2018 [Member] | Level 2 [Member] | Fair Value [Member]	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Debt and Capital Lease Obligations	574,840	[1]	570,429	[1]
$330 million notes at 4.875% due May 2023 [Member]	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Debt and Capital Lease Obligations	330,000		330,000
$330 million notes at 4.875% due May 2023 [Member] | Level 2 [Member] | Carrying Value [Member]	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Debt and Capital Lease Obligations	330,000		330,000
$330 million notes at 4.875% due May 2023 [Member] | Level 2 [Member] | Fair Value [Member]	'		'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'
Debt and Capital Lease Obligations	$311,025	[1]	$298,650	[1]
[1]	(1) The fair value of the notes is calculated based on indicated market values.

Income_Tax_Narrative_Details

Income Tax (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Income Tax Disclosure [Abstract]	'	'
Effective income tax rate from continuing operations	32.10%	31.20%
Effective income tax rate from discontinued operations	38.90%	37.00%
Net income tax payments	$1.40	$0.30
Gross unrecognized tax benefits	28.6	27.4
Possible unrecognized tax benefits reduction during the next twelve months	$17.90	'

Sharebased_Compensation_Plans_

Share-based Compensation Plans (Narrative) (Details) (USD $)	3 Months Ended		12 Months Ended
In Millions, except Share data, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012	Aug. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Share-based compensation expense	5.5	$4.50	'
SARs [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
SARs, granted, number	'	200,000	'
Granted, weighted average exercise price	'	$14.12	'
Vesting period in years	'	'	'3 years
Contractual term	'7 years	'	'
RSUs And PSUs [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Number of shares granted	1,100,000	1,300,000	'
Weighted average grant-date fair value	16.75	$12.99	'
Vesting period in years	'3 years	'	'
Certain RSUs [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Vesting period in years	'4 years	'	'
PSU [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Vesting period in years	'3 years	'	'3 years
Share-Based Liability Awards [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Number of shares granted	59,565	204,069	'
Equivalent number of shares outstanding	2,016,522	'	'
Equivalent number of shares expected to vest	1,717,684	'	'

Earnings_Per_Share_Attributabl2

Earnings Per Share Attributable To CMC (Calculations of the Basic and Diluted Earnings Per Share) (Details) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Earnings Per Share [Abstract]	'	'
Net earnings attributable to CMC	$45,919	$49,717
Basic earnings per share:	'	'
Shares outstanding for basic earnings per share	117,070,499	116,336,504
Basic earnings per share attributable to CMC:	$0.39	$0.43
Diluted earnings per share:	'	'
Shares outstanding for basic earnings per share	117,070,499	116,336,504
Effect of dilutive securities:	'	'
Share-based incentive/purchase plans	1,086,112	757,123
Shares outstanding for diluted earnings per share	118,156,611	117,093,627
Diluted earnings per share attributable to CMC:	$0.39	$0.42
Anti-dilutive shares not included above	1,364,036	2,945,188

Earnings_Per_Share_Attributabl3

Earnings Per Share Attributable To CMC (Narrative) (Details)	3 Months Ended
	Nov. 30, 2013
Earnings Per Share [Abstract]	'
Treasury Stock, Shares, Acquired	0
Remaining number of shares authorized to be purchased	8,259,647

Commitments_And_Contingencies_

Commitments And Contingencies (Narrative) (Details) (USD $)	Nov. 30, 2013	Sep. 18, 2008
In Millions, unless otherwise specified	states	entities
Guarantee of Indebtedness of Others [Member]	'	'
Loss Contingencies [Line Items]	'	'
Maximum credit facility	4	'
Guarantor obligations, maximum exposure	2.8	'
Class Action Antitrust Lawsuit [Member]	'	'
Loss Contingencies [Line Items]	'	'
Number of steel manufacturing companies	'	9
Number of states	28	'

Business_Segments_Narrative_De

Business Segments (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2013	Aug. 31, 2013
	segments	Segment, Discontinued Operations [Member]	Segment, Discontinued Operations [Member]
Number of operating segments	5	'	'
Total assets	'	$6.60	$50.50

Business_Segments_Summary_of_C

Business Segments (Summary of Certain Financial Information from Continuing Operations by Reportable Segment) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013		Nov. 30, 2012	Aug. 31, 2013
Segment Reporting Information [Line Items]	'		'	'
Net sales-unaffiliated customers	$1,682,891		$1,749,515	'
Adjusted operating profit (loss)	67,189		89,353	'
Segment, Continuing Operations [Member]	'		'	'
Segment Reporting Information [Line Items]	'		'	'
Net sales-unaffiliated customers	1,682,891		1,749,515	'
Intersegment sales	0		0	'
Net sales	1,682,891		1,749,515	'
Adjusted operating profit (loss)	67,189		89,353	'
Total assets	3,531,061	[1]	'	3,444,261	[1]
Americas Recycling [Member]	'		'	'
Segment Reporting Information [Line Items]	'		'	'
Net sales-unaffiliated customers	293,475		307,471	'
Intersegment sales	44,727		44,490	'
Net sales	338,202		351,961	'
Adjusted operating profit (loss)	839		4,494	'
Total assets	281,102	[1]	'	309,599	[1]
Americas Mills [Member]	'		'	'
Segment Reporting Information [Line Items]	'		'	'
Net sales-unaffiliated customers	291,573		267,105	'
Intersegment sales	189,578		189,633	'
Net sales	481,151		456,738	'
Adjusted operating profit (loss)	65,814		51,660	'
Total assets	594,224	[1]	'	598,478	[1]
Americas Fabrication [Member]	'		'	'
Segment Reporting Information [Line Items]	'		'	'
Net sales-unaffiliated customers	353,992		352,747	'
Intersegment sales	4,226		3,845	'
Net sales	358,218		356,592	'
Adjusted operating profit (loss)	2,217		10,192	'
Total assets	608,313	[1]	'	631,510	[1]
International Mill [Member]	'		'	'
Segment Reporting Information [Line Items]	'		'	'
Net sales-unaffiliated customers	228,492		215,858	'
Intersegment sales	658		6,209	'
Net sales	229,150		222,067	'
Adjusted operating profit (loss)	15,268		876	'
Total assets	499,366	[1]	'	487,613	[1]
International Marketing and Distribution [Member]	'		'	'
Segment Reporting Information [Line Items]	'		'	'
Net sales-unaffiliated customers	509,174		603,535	'
Intersegment sales	1,984		5,053	'
Net sales	511,158		608,588	'
Adjusted operating profit (loss)	503		40,161	'
Total assets	858,567	[1]	'	838,413	[1]
Corporate [Member]	'		'	'
Segment Reporting Information [Line Items]	'		'	'
Net sales-unaffiliated customers	6,185		2,799	'
Intersegment sales	0		0	'
Net sales	6,185		2,799	'
Adjusted operating profit (loss)	-18,049		-17,370	'
Total assets	1,182,688	[1]	'	1,075,594	[1]
Eliminations [Member]	'		'	'
Segment Reporting Information [Line Items]	'		'	'
Net sales-unaffiliated customers	0		0	'
Intersegment sales	-241,173		-249,230	'
Net sales	-241,173		-249,230	'
Adjusted operating profit (loss)	597		-660	'
Total assets	($493,199)	[1]	'	($496,946)	[1]
[1]	Excludes total assets from discontinued operations of $6.6 million at NovemberB 30, 2013 and $50.5 million at AugustB 31, 2013.

Business_Segments_Reconciliati

Business Segments (Reconciliations of Earnings from Continuing Operations to Adjusted Operating Profit) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Segment Reporting [Abstract]	'	'
Earnings from continuing operations	$31,961	$48,931
Income taxes	15,091	22,189
Interest expense	19,578	17,024
Discounts on sales of accounts receivable	559	1,209
Adjusted operating profit	$67,189	$89,353