Notes Payable (Detail Textuals) - Senior secured credit facility - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jul. 31, 2016	Jul. 31, 2015
Debt Instrument [Line Items]
Term of senior secured credit facility	5 years
Senior secured credit facility	$ 450.0
Amount available under credit agreement	$ 343.4
Line of credit outstanding amount		$ 5.5
LIBOR plus \| Minimum
Debt Instrument [Line Items]
Spread interest rate	1.50%
LIBOR plus \| Maximum
Debt Instrument [Line Items]
Spread interest rate	2.00%
Prime plus \| Minimum
Debt Instrument [Line Items]
Spread interest rate	0.50%
Prime plus \| Maximum
Debt Instrument [Line Items]
Spread interest rate	1.00%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Period Type:	duration

- 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.

+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

Average amount borrowed under the credit facility during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Period Type:	instant

- Details

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- Details

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- Details

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