Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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- Definition

Date the debt instrument was issued, in CCYY-MM-DD format.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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-Publisher FASB
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Date the credit facility first became available, in CCYY-MM-DD format.

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- Definition

The effective interest rate at the end of the reporting period.

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

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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-Paragraph 20, 22
-Article 5

+ Details

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- Details

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- Details

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Credit Arrangements (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Aug. 31, 2016	Aug. 31, 2015	Feb. 19, 2015	Feb. 18, 2015
Debt Instrument [Line Items]
Long-term Debt	$ 117,173	$ 117,366
Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 115,000	115,000
Face amount			$ 115,000
Issuance date	Feb. 19, 2015
Maturity date	Feb. 19, 2030
Debt Instrument, Interest Rate, Stated Percentage			3.82%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Initiation date	Feb. 18, 2015
Maturity date	Feb. 18, 2018
Unsecured revolving line of credit, maximum borrowing capacity				$ 50,000
Unsecured revolving line of credit, amount outstanding	$ 0	0
Line of Credit Facility, Remaining Borrowing Capacity	$ 43,900
Interest rate	1.42%
Annual commitment fee	0.25%
Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis points	0.90%
Revolving Credit Facility [Member] \| Standby Letters of Credit [Member]
Debt Instrument [Line Items]
Unsecured revolving line of credit, amount outstanding	$ 6,100
Series 2006A Bonds [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 2,200
Maturity date	Sep. 01, 2026
Series 2006A Bonds [Member] \| Five Year United States Treasury Notes [Member]
Debt Instrument [Line Items]
Basis points	0.45%
Interest rate	1.64%
Series 2006A Bonds [Member] \| Revolving Credit Facility [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 2,173	$ 2,366