Employee Stock Purchase Plan Limitation Stock Fair Market Value, Maximum

No definition available.

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- Definition

Final price paid per share for the purchase of the targeted number of shares, determined by an average market price over a fixed period of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 25
-Paragraph 5
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- Definition

Amount of cash receipt from (payment to) bank; or stock received from (issuance to) bank in the settlement of the accelerated share repurchase agreement.

+ References

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- Definition

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

+ References

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB
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-Section 50
-Paragraph 2
-Subparagraph (i)
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

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- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 15
-Subparagraph (a)
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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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- Definition

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.

+ References

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- Definition

Period 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, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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- Definition

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.

+ References

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

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

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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-Publisher FASB
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- Definition

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

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- Definition

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 (Deficit) (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands	1 Months Ended					3 Months Ended												12 Months Ended
	Oct. 27, 2017	Jul. 31, 2015	Feb. 28, 2015	Jan. 31, 2015	Oct. 31, 2014	Aug. 31, 2017	May 31, 2017	Feb. 28, 2017	Nov. 30, 2016	Aug. 31, 2016	May 31, 2016	Feb. 29, 2016	Nov. 30, 2015	Aug. 31, 2015	May 31, 2015	Feb. 28, 2015	Nov. 30, 2014	Aug. 31, 2017	Aug. 31, 2016	Aug. 31, 2015	Oct. 31, 2016	Aug. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation cost recognized																		$ 3,942,000	$ 3,766,000	$ 3,520,000
Excess tax benefits																		1,300,000	$ 1,200,000	$ 1,000,000
Unvested unrecognized compensation cost						$ 7,500,000												$ 7,500,000
Unvested unrecognized compensation cost, period																		1 year 10 months 24 days
Weighted average fair value of stock options granted																		$ 6.65	$ 8.23	$ 8.83
Proceeds from exercise of stock options																		$ 2,682,000	$ 3,842,000	$ 18,732,000
Total intrinsic value of options exercised																		4,600,000	18,900,000	21,800,000
Shares repurchase authorized amount						160,000,000					$ 155,000,000			$ 145,000,000.0				160,000,000		145,000,000.0	$ 40,000,000	$ 105,000,000.0
Total cost for shares acquired through stock repurchase program																		$ 172,913,000	$ 148,345,000	$ 123,786,000
Weighted-average price per share																		$ 25.71	$ 28.48	$ 29.46
Remaining amount authorized for repurchase through stock repurchase program						$ 160,000,000												$ 160,000,000
Cash dividends declared per common share						$ 0.14	$ 0.14	$ 0.14	$ 0.14	$ 0.11	$ 0.11	$ 0.11	$ 0.11	$ 0.09	$ 0.09	$ 0.09	$ 0.09	$ 0.56	$ 0.44	$ 0.27
Payment of dividends																		$ 24,062,000	$ 21,309,000	$ 18,808,000
Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash dividends declared per common share	$ 0.16
Dividends payable, date of record	Nov. 08, 2017
Dividends payable, date to be paid	Nov. 17, 2017
October 2014 Accelerated Share Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares repurchase authorized amount					$ 15,000,000.0
Total cost for shares acquired through stock repurchase program					$ 15,000,000
Shares acquired through stock repurchase program				0	600
Cash payment at completion of accelerated share repurchase program				$ 100,000
Final price paid per share				$ 26.32
February 2015 Accelerated Share Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares repurchase authorized amount			$ 75,000,000.0													$ 75,000,000.0
Total cost for shares acquired through stock repurchase program			$ 75,000,000
Shares acquired through stock repurchase program		300	2,100
Final price paid per share		$ 31.38
Treasury Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total cost for shares acquired through stock repurchase program																		$ 172,913,000	$ 148,345,000	$ 123,786,000
Shares acquired through stock repurchase program																		6,726	5,209	4,201
2006 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant						6,500												6,500
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term																		7 years
Vesting period																		3 years
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period																		3 years
Aggregate fair value of vested restricted stock																		$ 500,000	$ 400,000	$ 1,100,000
Board of Director Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term																		7 years
Vesting period																		1 year
Board of Director Restricted Stock Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period																		1 year
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount price percentage																		15.00%
Compensation percentage						10.00%												10.00%
Stock’s fair market value						$ 25,000												$ 25,000
Shares available for grant						800												800