Stock-Based Compensation - Performance-based Awards (Details)	1 Months Ended	3 Months Ended
Oct. 31, 2016 USD ($) shares	Oct. 31, 2016 USD ($)
Stock-based awards, additional disclosure
Total unrecognized stock-based compensation expense, before income taxes, related to total nonvested stock options and stock awards (in dollars) \| $	$ 14,242,000	$ 14,242,000
Remaining weighted average period over which unrecognized stock-based compensation expense is expected to be recognized		25 months
Performance Share Units
Stock-based awards, additional disclosure
Maximum attainment of initial grant (as a percent)	200.00%	200.00%
Performance Share Units, Based on budgeted revenue and gross profit percentage
Stock-based awards, additional disclosure
Granted (in shares)	12,810
Performance Shares Units, Based on market conditions
Stock-based awards, additional disclosure
Granted (in shares)	9,800
Vesting period	3 years

The percentage of maximum attainment of initial grant .

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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

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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

+ Details

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- References

No definition available.

+ 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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