Beneficially ownership in company's outstanding common stock to be held by person or group to exercise rights.

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- Definition

Business days after the commencement of a tender or exchange offer during which rights to be exercised.

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Calendar days after a public announcement during which rights to be exercised.

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- Definition

Purchase price for right holders.

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- Definition

Stockholders' equity.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.4-08.(i)(4))
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- Definition

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

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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-Name Accounting Standards Codification
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- Definition

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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- Definition

Number of shares issued for each share of convertible preferred stock that is converted.

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- Definition

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

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- Definition

Maximum number of excess stock shares permitted to be issued.

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No definition available.

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- Definition

The cash outflow to reacquire common stock during the period.

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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.

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No definition available.

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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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No definition available.

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

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended												12 Months Ended
	Nov. 30, 2018	Aug. 31, 2018	May 31, 2018	Feb. 28, 2018	Nov. 30, 2017	Aug. 31, 2017	May 31, 2017	Feb. 28, 2017	Nov. 30, 2016	Aug. 31, 2016	May 31, 2016	Feb. 29, 2016	Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2016	May 14, 2018	Jan. 12, 2016	Nov. 30, 2015	Jul. 17, 2014	Jan. 29, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized	290,000,000				290,000,000								290,000,000	290,000,000
Authorized repurchase of common stock																		4,000,000
Excess Stock, Shares Authorized																2,373,000
Common Stock, Shares, Issued	119,195,914				117,945,525								119,195,914	117,945,525
Stock repurchases													$ 35,039	$ 0	$ 85,938
Treasury stock, Value													$ 8,476	6,673	$ 2,421
Stockholder's Equity (Textual) [Abstract]
Number of shares that can be purchased by exercising each right	0.01												0.01
Purchase price for right holders	$ 85.00												$ 85.00
Calendar days after a public announcement during which rights to be exercised													10 days
Business days after the commencement of a tender or exchange offer during which rights to be exercised													10 days
Beneficially ownership in company's outstanding common stock to be held by person or group to exercise rights													4.90%
Price at which company may redeem all of the then outstanding rights	0.001												$ 0.001
Cash dividend declared per share	$ 0.025	$ 0.025	$ 0.025	$ 0.025	$ 0.025	$ 0.025	$ 0.025	$ 0.025	$ 0.025	$ 0.025	$ 0.025	$ 0.025
Director Plan SARs [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized																			680,000
Authorized repurchase of common stock																			680,000
Common Stock, Shares, Issued	0												0
January 2016 Stock Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized repurchase of common stock																4,000,000	10,000,000
Treasury Stock, Shares, Acquired													1,806,053		8,373,000
Stock repurchases													$ 35,000		$ 85,900
Not Part of a Share Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury stock, Value													$ 8,500	$ 6,700	$ 2,400
Convertible senior notes due February 1, 2019 at 1.375%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.375%												1.375%							1.375%