XML 37 R56.htm IDEA: XBRL DOCUMENT v2.4.1.9

Capital Stock (Details) (USD $)	3 Months Ended	6 Months Ended		12 Months Ended
	Jan. 24, 2015	Jan. 24, 2015	Jan. 25, 2014	Jul. 26, 2014	Feb. 24, 2015	Aug. 27, 2013
Class of Stock [Line Items]
Number of Shares Repurchased	488,768us-gaap_StockRepurchasedDuringPeriodShares			360,900us-gaap_StockRepurchasedDuringPeriodShares
Average Price Per Share (in dollars per share)	$ 35.08dy_AveragePricePerShareRepurchaseOfCommonStock			$ 27.71dy_AveragePricePerShareRepurchaseOfCommonStock
Total Consideration (Dollars in thousands)	$ 17,100,000us-gaap_PaymentsForRepurchaseOfCommonStock	$ 17,147,000us-gaap_PaymentsForRepurchaseOfCommonStock	$ 9,999,000us-gaap_PaymentsForRepurchaseOfCommonStock	$ 10,000,000us-gaap_PaymentsForRepurchaseOfCommonStock
Shares Paid for Tax Withholding for Share Based Compensation		138,535us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation	130,195us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation
Value of Shares Paid for Tax Withholding for Share Based Compensation		4,300,000dy_ValueofSharesPaidforTaxWithholdingforShareBasedCompensation	3,600,000dy_ValueofSharesPaidforTaxWithholdingforShareBasedCompensation
Common Stock
Class of Stock [Line Items]
Remaining authorized repurchase amount	12,900,000us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1 / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember	12,900,000us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1 / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember
Common stock authorized repurchase amount					$ 40,000,000us-gaap_StockRepurchaseProgramAuthorizedAmount1 / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember	$ 40,000,000us-gaap_StockRepurchaseProgramAuthorizedAmount1 / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember

X

- Definition

The total costs of shares repurchased during the period divided by the total number of shares that have been repurchased during the period which have not been retired and are not held in treasury.

+ References

No definition available.

+ Details

Name:	dy_AveragePricePerShareRepurchaseOfCommonStock
Namespace Prefix:	dy_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

X

- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the monetary value of shares the employees use to repay the employer.

+ References

No definition available.

+ Details

Name:	dy_ValueofSharesPaidforTaxWithholdingforShareBasedCompensation
Namespace Prefix:	dy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	us-gaap_ClassOfStockLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The cash outflow to reacquire common stock during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

+ Details

Name:	us-gaap_PaymentsForRepurchaseOfCommonStock
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

+ Details

Name:	us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644



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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

+ Details

Name:	us-gaap_StockRepurchasedDuringPeriodShares
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

Name:	us-gaap_StockRepurchaseProgramAuthorizedAmount1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

+ Details

Name:	us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: