Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Nov. 30, 2013
Income Taxes [Abstract]
Unrecognized tax benefits	$ 2.1
Unrecognized tax benefits in interest and penalties	0.3
Decrease in unrecognized tax benefits	0.5
Possible change in unrecognized tax benefits, lower bound	1.3
Possible change in unrecognized tax benefits, upper bound	(1.5)
Tax benefit resulting from the IRS' acceptance of a federal tax method change	$ 0.5

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The estimated lower bound of the reasonably possible change in the total amount of the unrecognized tax benefit (that will significantly increase or decrease within twelve months of the balance sheet date) for a tax position taken.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (d)

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The estimated upper bound of the reasonably possible change in the total amount of the unrecognized tax benefit (that will significantly increase or decrease within twelve months of the balance sheet date) for a tax position taken.

+ References

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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 25

-Paragraph 8

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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-Publisher FASB

-Name Accounting Standards Codification

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The net amount of all increases and decreases in unrecognized tax benefits for the period.

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-Name Accounting Standards Codification

-Topic 740

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