XML 113 R98.htm IDEA: XBRL DOCUMENT
v3.7.0.1

Quarterly Financial Data (Unaudited) - Narratives (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Oct. 24, 2015 | Jul. 29, 2017 | Jul. 15, 2015
Interim Period, Costs Not Allocable [Line Items] |  |  |
Debt extinguishment cost | $ 16.3 |  |
7.125% Senior Subordinated Notes |  |  |
Interim Period, Costs Not Allocable [Line Items] |  |  |
Debt, interest rate (in percent) | 7.125% | 7.125% | 7.125%

X
- Definition Debt Extinguishment Cost + References No definition available. + Details
Name: | dy_DebtExtinguishmentCost
Namespace Prefix: | dy_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: 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 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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_InterimPeriodCostsNotAllocableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_DebtInstrumentAxis=dy_SevenPointOneTwoFivePercentSeniorSubordinatedNotesDue2021Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |