Number of consecutive years vesting continues after the initial vest date.

No definition available.

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- Definition

The number of years after the grant date that vesting starts.

+ References

No definition available.

+ Details

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- Definition

Maximum 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

+ References

No definition available.

+ Details

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- Definition

Mininimum 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

+ References

No definition available.

+ Details

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- Definition

Percent of share based compensation that vests annually.

+ References

No definition available.

+ Details

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=6793087&loc=d3e301413-122809

+ Details

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

+ References

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

+ References

+ Details

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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.

+ References

+ Details

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Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Details

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Data Type:	xbrli:sharesItemType
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Period Type:	instant

- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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Stock-Based Compensation Narrative (Details) (USD $)	3 Months Ended		9 Months Ended
Stock-Based Compensation Narrative (Details) (USD $)	Apr. 30, 2013	Apr. 30, 2012	Apr. 30, 2013	Apr. 30, 2012
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Cash Received from Exercise of Stock Options	$ 34,000	$ 71,000	$ 686,000	$ 192,000
Tax Benefit Realized from Exercise of Stock Options	16,000	24,000	284,000	89,000
Options, Granted (shares)			0	0
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Restricted Stock Granted, Number (shares)			20,000
Directors' Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Number available for grant (shares)	0		0
Award Vesting Period (Years)			1 year
2006 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number Authorized (shares)	937,500		937,500
2006 Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Award Vesting Period, Minimum (years)			2 years
Award Vesting Period, Maximum (years)			5 years
Share-based Compensation Expense	$ 203,000	$ 179,000	$ 616,000	$ 513,000
2006 Plan - Director Stock Option \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Award Vesting Period (Years)			1 year
2006 Plan - Employee Stock Options \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Annual Vesting Percentage			25.00%
Number of years after grant date vesting starts (years)			2 years
Number of consecutive years vesting occurs after initial vest date (years)			3 years
1995 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number available for grant (shares)	0		0
1995 Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Annual Vesting Percentage			25.00%
Number of years after grant date vesting starts (years)			2 years
Number of consecutive years vesting occurs after initial vest date (years)			3 years
Common Stock \| 2006 Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Restricted Stock Granted, Number (shares)	13,000	18,000
Common Class B \| 2006 Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Restricted Stock Granted, Number (shares)		2,000