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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

+ References

No definition available.

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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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- Definition

Identifies or describes the benchmark that serves as the denominator in the calculation of the percentage of concentration risk.

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- Definition

Description of risks that arise due to the volume of business transacted with a particular customer. At a minimum, the description informs financial statement users of the general nature of the risk, but excludes "Information about Major Customers" that may be disclosed elsewhere (for instance, segment disclosures).

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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No definition available.

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- Definition

The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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No definition available.

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The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

For each plan, identification of the award pricing model or other valuation method used in calculating the weighted average fair values disclosed. The model is also used to calculate the compensation expense that is shown within the balance sheet, income statement, and cash flow. Examples of valuation techniques are lattice models (binomial model), closed-form models (Black-Scholes-Merton formula), and a Monte Carlo simulation technique. Fair value is the amount at which an asset or liability could be bought or incurred or sold or settled in a current transaction between willing parties, that is, other than in a forced or liquidation sale. May include disclosures about the assumptions underlying application of the method selected.

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

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No definition available.

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- Definition

The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

No definition available.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Acquisitions (Details Textuals) $ in Thousands	12 Months Ended
Acquisitions (Details Textuals) $ in Thousands	Jul. 31, 2017 USD ($) business customer	Jul. 31, 2016 USD ($) business customer	Jul. 31, 2015 USD ($) business customer
Business Acquisition [Line Items]
Number of Businesses Acquired \| business	2	0	0
Business Combination, Separately Recognized Transactions, Additional Disclosures, Acquisition Cost Expensed	$ 1,900	$ 0	$ 0
Goodwill	340,243	260,198	$ 271,850
Intangibles, net	$ 75,938	$ 11,761
Covenants not to compete
Business Acquisition [Line Items]
Useful life of intangible assets	1 year	2 years
Intangibles, net	$ 313	$ 467
Licenses and databases
Business Acquisition [Line Items]
Useful life of intangible assets	3 years	1 year
Intangibles, net	$ 3,541	$ 135
Acquisitions 2017 \| Supply contracts \| Minimum
Business Acquisition [Line Items]
Useful life of intangible assets	3 years
Acquisitions 2017 \| Supply contracts \| Maximum
Business Acquisition [Line Items]
Useful life of intangible assets	11 years
Acquisitions 2017 \| Customer relationships \| Minimum
Business Acquisition [Line Items]
Useful life of intangible assets	3 years
Acquisitions 2017 \| Customer relationships \| Maximum
Business Acquisition [Line Items]
Useful life of intangible assets	11 years
Acquisitions 2017 \| Trade name \| Minimum
Business Acquisition [Line Items]
Useful life of intangible assets	3 years
Acquisitions 2017 \| Trade name \| Maximum
Business Acquisition [Line Items]
Useful life of intangible assets	11 years
Acquisitions 2017 \| Licenses and databases \| Minimum
Business Acquisition [Line Items]
Useful life of intangible assets	3 years
Acquisitions 2017 \| Licenses and databases \| Maximum
Business Acquisition [Line Items]
Useful life of intangible assets	11 years
Sales Revenue, Net [Member]
Business Acquisition [Line Items]
Concentration risk, benchmark description	more than 10	more than 10	more than 10
Concentration Risk, Customer	No single customer accounted for more than 10	no single customer accounted for more than 10	no single customer accounted for more than 10
Number of Customers Exceeding Threshold \| customer	0	0	0
Accounts Receivable [Member]
Business Acquisition [Line Items]
Concentration risk, benchmark description	more than 10	more than 10
Concentration Risk, Customer	no customer accounted for more than 10%	one customer accounted for more than 10
Number of Customers Exceeding Threshold \| customer	0	1
Employee Stock Option [Member]
Business Acquisition [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum	23.00%	26.00%	28.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Method Used	Black-Scholes Merton (BSM) option-pricing model	Black-Scholes Merton (BSM) option-pricing model	Black-Scholes Merton (BSM) option-pricing model
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum	1.20%	1.16%	1.58%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum	2.07%	2.06%	2.26%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum	20.00%	21.00%	22.00%
Employee Stock Option [Member] \| Minimum
Business Acquisition [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	5 years 6 months	5 years 3 months 18 days	5 years 3 months 18 days
Employee Stock Option [Member] \| Maximum
Business Acquisition [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	7 years 4 months 24 days	7 years 2 months 12 days	7 years 2 months 12 days
Office Equipment [Member] \| Minimum
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Office Equipment [Member] \| Maximum
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Building and Building Improvements [Member] \| Minimum
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Building and Building Improvements [Member] \| Maximum
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life	40 years
Leasehold Improvements [Member] \| Minimum
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Leasehold Improvements [Member] \| Maximum
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Software and Software Development Costs [Member] \| Minimum
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Software and Software Development Costs [Member] \| Maximum
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life	7 years
Transportation Equipment [Member] \| Minimum
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Transportation Equipment [Member] \| Maximum
Business Acquisition [Line Items]
Property, Plant and Equipment, Useful Life	20 years