Aggregate number of common shares reserved for future issuance.

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Aggregate dividends paid during the period for each share of common stock outstanding.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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

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Maximum number of excess stock shares permitted to be issued.

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The cash outflow to reacquire common stock during the period.

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Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Stockholders' Equity (Narratives) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2018	Aug. 31, 2017	Nov. 30, 2016	May 14, 2018	Feb. 14, 2018	Nov. 30, 2017	Jan. 12, 2016	Jul. 17, 2014
Debt Instrument [Line Items]
Common stock reserve (in shares)	12,602,735		12,602,735
Additional shares authorized to be repurchased (in shares)						2,373,000
Payments Related to Tax Withholding for Share-based Compensation			$ 6,787	$ 2,543
Dividend paid in each quarter (in dollars per share)	$ 0.0250	$ 0.0250	$ 0.075	$ 0.075
January 2016 Stock Repurchase Program [Member]
Debt Instrument [Line Items]
Number of common stock, authorized, approved under a board approved stock repurchase program (in shares)	4,000,000		4,000,000						10,000,000
Stock repurchases					$ 85,900
Common stock repurchased (in shares)					8,373,000
Shares Withheld to Pay Taxes [Member]
Debt Instrument [Line Items]
Common stock repurchased (in shares)			217,006
Payments Related to Tax Withholding for Share-based Compensation			$ 6,800
PSU 2014 [Domain] \| Performance Shares [Member]
Debt Instrument [Line Items]
Common Stock, Shares, Issued (in shares)							437,689
Director Plan SARs [Domain]
Debt Instrument [Line Items]
Number of common stock, authorized, approved under a board approved stock repurchase program (in shares)										680,000
Convertible Notes Payable [Member] \| Convertible Senior Notes Due Two Thousand Nineteen At One Point Three Seven Five Percent [Member]
Debt Instrument [Line Items]
Senior notes, rate	1.375%		1.375%					1.375%