Number of Subsidiaries

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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- Definition

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Period Type:	instant

- Definition

Aggregate revenue during the period from services rendered in the normal course of business, after deducting allowances and discounts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(d))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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- Details

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Basis of Presentation and Accounting Policies (Details) (USD $)	3 Months Ended		6 Months Ended
	Jan. 24, 2015 subsidiary segment	Jan. 25, 2014	Jan. 24, 2015	Jan. 25, 2014	Jul. 26, 2014
Segment Reporting Information [Line Items]
Number of reportable segments	1us-gaap_NumberOfReportableSegments
Number of subsidiaries	2dy_NumberofSubsidiaries
Contract revenues	$ 441,081,000us-gaap_SalesRevenueServicesNet	$ 390,518,000us-gaap_SalesRevenueServicesNet	$ 951,470,000us-gaap_SalesRevenueServicesNet	$ 903,238,000us-gaap_SalesRevenueServicesNet
Restricted cash	4,500,000		4,500,000		4,000,000
Senior Subordinated Notes \| 7.125% Senior Subordinated Notes Due 2021
Segment Reporting Information [Line Items]
Debt, interest rate (in percent)	7.125%		7.125%		7.125%
Canada
Segment Reporting Information [Line Items]
Contract revenues	$ 3,100,000	$ 2,100,000	$ 7,800,000	$ 5,400,000