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Carrying value as of the balance sheet date of obligations incurred through that date and payable to insurance entities and/or claimants to mitigate potential losses from auto liability, general liability, workers compensation, employee group health, and damage claims. Used to reflect the Noncurrent portion of the liabilities.

+ References

No definition available.

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- Definition

Aggregate Stop Loss Coverage for Automobile Liability, General Liability, and Workers' Compensation Claims Before Adjustment Increase

+ References

No definition available.

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- Definition

The maximum retained risk of loss per occurrence for automobile liability.

+ References

No definition available.

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- Definition

Annual retained risk of loss under the employee health plan.

+ References

No definition available.

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- Definition

Threshold for retained risk of loss per participant for employee health plan

+ References

No definition available.

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- Definition

Retained risk of loss per participant for employee health plan for claim amounts that aggregate across all participants in excess of $250,000

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable to insurance entities to mitigate potential loss from various risks or to satisfy a promise to provide certain coverage's to employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph a

-Article 7

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph 5

-Article 9

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Accrued Insurance Claims (Details) (USD $)	Jan. 24, 2015	Jul. 26, 2014	Jul. 25, 2015
Accrued Insurance Claims [Line Items]
Insurance liability, annual retained risk loss	$ 250,000
Retained risk of loss per participant for employee health plan for claim amounts that aggregate across all participants in excess of $250,000	550,000
Health plan participant threshold	250,000
Accrued Insurance	72,500,000	66,000,000
Accrued insurance claims, Noncurrent	38,348,000dy_AccruedInsuranceClaimsNoncurrent	33,782,000dy_AccruedInsuranceClaimsNoncurrent
Scenario, Forecast
Accrued Insurance Claims [Line Items]
Aggregate stop loss coverage for automobile liability, general liability, and workers' compensation claims before adjustment			59,500,000
Maximum
Accrued Insurance Claims [Line Items]
Retained risk of loss, general liability and workers' compensation, maximum automobile liability	$ 1,000,000