XML 65 R50.htm IDEA: XBRL DOCUMENT
v3.7.0.1

Basis of Presentation and Accounting Policies - Accrued Insurance Claims (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Jul. 29, 2017 | Jul. 30, 2016
Condensed Balance Sheet Statements, Captions [Line Items] |  |
Accrued insurance | $ 101.9 | $ 89.7
Losses incurred but not recognized from insurance claims | 50.0 | 44.5
Other Noncurrent assets |  |
Condensed Balance Sheet Statements, Captions [Line Items] |  |
Insurance recoveries/receivables related to accrued claims | $ 9.2 | $ 5.7

X
- Definition Losses Incurred but not Recognized from Insurance Claims + References No definition available. + Details
Name: | dy_LossesIncurredbutnotRecognizedfromInsuranceClaims
Namespace Prefix: | dy_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- 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 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: 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 3: 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(20)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 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 210.7-03(a)(15)(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
Name: | us-gaap_AccruedInsuranceCurrentAndNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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_CondensedBalanceSheetStatementsCaptionsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy. + References No definition available. + Details
Name: | us-gaap_InsuranceSettlementsReceivable
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=us-gaap_OtherNoncurrentAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |