Employee Benefit Plans (Narrative) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Apr. 30, 2015 agreement
Defined Benefit Plan Disclosure [Line Items]
Number of U.S. plans	2dci_NumberOfUsPlans
Employees Hired On Or After August 1, 2013 Will Be Eligible For Retirement Contribution [Member]
Defined Benefit Plan Disclosure [Line Items]
Annual Company retirement contribution in addition to 401 (k) match, percent	3.00%
Employees Hired Prior To August 1, 2013 Will Be Eligible For Retirement Contribution, Effective August 1, 2016 [Member]
Defined Benefit Plan Disclosure [Line Items]
Annual Company retirement contribution in addition to 401 (k) match, percent	3.00%
U.S. Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Company contributions	1.6
Estimated future contributions to pension plans	12.1
Expense related to lump sum settlement	3.9
Non-U.S. Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Company contributions	2.8
Additional future contribution towards pension plans for the remainder of Fiscal 2015	0.7

Additional contributions to pension plans.

No definition available.

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- Definition

Defined contribution plan, annual retirement contributions, percent.

+ References

No definition available.

+ Details

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- Definition

Number Of U.S. Plans.

+ References

No definition available.

+ Details

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

The amount of pension benefit costs recognized during the period for (1) defined benefit plans and (2) defined contribution plans. For defined benefit plans, pension expense includes the following components: service cost, interest cost, expected return on plan assets, gain (loss) on plan assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. For defined contribution plans, the pension expense generally equals the firm's contribution to employees' accounts (if the firm contributes) during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

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