STOCK BASED COMPENSATION Stock compensation expense (Details) (USD $)	12 Months Ended
Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	2,350,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period, Minimum	five
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Date	six
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period, Maximum	ten
Common Stock, Capital Shares Reserved for Future Issuance	194,925	553,345	577,668
Options granted to directors	$ 107,000	$ 55,000	$ 40,000
Restricted stock awards	4,834,000	3,780,000	3,670,000
Restricted stock units	528,000	202,000	68,000
Stock-based compensation expense	5,469,000	4,037,000	3,778,000
Remaining unrecognized compensation cost (in thousands)	25,543,000	8,319,000	8,598,000
Weighted average period of time over which this cost will be recognized (years)	7.8	3.2	3.0
Excess tax benefit (deficiency) on stock-based compensation (in thousands)	1,438,000	752,000	(57,000)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Grants outstanding at beginning of period	436,611	558,821	618,250
Granted	399,041	95,700	151,930
Forfeited	(5,230)	(8,231)	(4,971)
Vested	(129,529)	(209,679)	(206,388)
Grants outstanding at end of period	700,893	436,611	558,821
Restricted stock awards and units granted	$ 67.26	$ 41.25	$ 23.36
Restricted stock awards and units vested	$ 23.46	$ 16.72	$ 16.58
Restricted stock awards and units forfeited	$ 29.30	$ 23.58	$ 18.69
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value	8,800,000	8,300,000	4,200,000
Treasury Stock, Shares, Acquired	46,373	69,146	70,679
Treasury Stock, Value, Acquired, Cost Method	$ 3,200,000	$ 2,700,000	$ 1,400,000
Stock Issued During Period, Shares, Treasury Stock Reissued	196,850
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	36,000	30,800	35,200
ShareBasedCompensation for options	2.00%	1.40%	1.10%

The noncash expense that represents the cost of restricted stock award distributed to employees as compensation.

No definition available.

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- Definition

The noncash expense that represents the cost of restricted stock units distributed to employees as compensation.

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Purchased for Award, Amount

+ References

No definition available.

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- Definition

Share Based Compensation for options percent to total stock based compensation

+ References

No definition available.

+ Details

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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- Definition

The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

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- Definition

Reductions in the entity's income taxes that arise when compensation cost (from non-qualified share-based compensation) recognized on the entity's tax return exceeds compensation cost from equity-based compensation recognized in financial statements. This element represents the cash inflow reported in the enterprise's financing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph i

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-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 00-15

-Paragraph 3

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 20

-Section 55

-Paragraph 24

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

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-Publisher FASB

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-Topic 230

-SubTopic 10

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-Paragraph 28

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- Definition

The date when the equity-based award expires as specified in the award agreement, which may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

+ References

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The maximum vesting term over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition.

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No definition available.

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The minimum vesting term over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition.

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No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

The weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect during the reporting period as a result of the occurrence of a terminating event specified in the contractual agreement of the plan.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

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-Paragraph A240

-Subparagraph c(1)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Publisher FASB

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-Paragraph A240

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

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-Publisher FASB

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-Paragraph A240

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-Publisher FASB

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-Paragraph A240

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- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

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-Publisher FASB

-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Paragraph A240

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Number of treasury shares (units) reissued during the period, excluding reissuance of shares (units) held in treasury used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

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- Definition

The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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