XML 94 R77.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Debt - Interest Rates of the Credit Agreement (Details) | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jan. 27, 2018 | Jul. 29, 2017 | Jul. 30, 2016
Credit Agreement - Revolving facility (matures April 2020) |  |  |
Line of Credit Facility [Line Items] |  |  |
Unutilized commitment fee (in percent) | 0.35% | 0.35% | 0.40%
Minimum | Standby Letters of Credit |  |  |
Line of Credit Facility [Line Items] |  |  |
Unutilized commitment fee (in percent) | 1.25% |  |
Minimum | Commercial Letters of Credit |  |  |
Line of Credit Facility [Line Items] |  |  |
Unutilized commitment fee (in percent) | 0.625% |  |
Minimum | Credit Agreement - Revolving facility (matures April 2020) |  |  |
Line of Credit Facility [Line Items] |  |  |
Unutilized commitment fee (in percent) | 0.25% |  |
Maximum | Standby Letters of Credit |  |  |
Line of Credit Facility [Line Items] |  |  |
Unutilized commitment fee (in percent) | 2.00% |  |
Maximum | Commercial Letters of Credit |  |  |
Line of Credit Facility [Line Items] |  |  |
Unutilized commitment fee (in percent) | 1.00% |  |
Maximum | Credit Agreement - Revolving facility (matures April 2020) |  |  |
Line of Credit Facility [Line Items] |  |  |
Unutilized commitment fee (in percent) | 0.40% |  |
Eurodollar |  |  |
Line of Credit Facility [Line Items] |  |  |
Basis spread on variable rate | 1.00% |  |
Eurodollar | Minimum |  |  |
Line of Credit Facility [Line Items] |  |  |
Basis spread on variable rate | 1.25% |  |
Eurodollar | Maximum |  |  |
Line of Credit Facility [Line Items] |  |  |
Basis spread on variable rate | 2.00% |  |
Administrative Agent Base Rate | Minimum |  |  |
Line of Credit Facility [Line Items] |  |  |
Basis spread on variable rate | 0.25% |  |
Administrative Agent Base Rate | Maximum |  |  |
Line of Credit Facility [Line Items] |  |  |
Basis spread on variable rate | 1.00% |  |
Federal Funds |  |  |
Line of Credit Facility [Line Items] |  |  |
Basis spread on variable rate | 0.50% |  |

X
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_LineOfCreditFacilityLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility. + References No definition available. + Details
Name: | us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreditFacilityAxis=us-gaap_StandbyLettersOfCreditMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreditFacilityAxis=dy_CommercialLettersofCreditMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_EurodollarMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=dy_AdministrativeAgentBaseRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_FederalFundsEffectiveSwapRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |