Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	Apr. 27, 2024	Jan. 27, 2024
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	$ 372,892	$ 367,542
Accumulated Amortization	264,427	258,588
Intangible Assets, Net	108,465	108,954
UtiliQuest
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	4,700	4,700
Accumulated Amortization	0	0
Intangible Assets, Net	$ 4,700	4,700
Customer relationships
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Useful life	7 years 10 months 24 days
Intangible Assets, Gross (Excluding Goodwill)	$ 342,817	338,117
Accumulated Amortization	249,964	245,512
Intangible Assets, Net	$ 92,853	92,605
Trade names
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Useful life	8 years 10 months 24 days
Intangible Assets, Gross (Excluding Goodwill)	$ 13,410	13,050
Accumulated Amortization	8,852	8,723
Intangible Assets, Net	$ 4,558	4,327
Backlog intangibles
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Useful life	2 years 3 months 18 days
Intangible Assets, Gross (Excluding Goodwill)	$ 11,890	11,600
Accumulated Amortization	5,589	4,335
Intangible Assets, Net	$ 6,301	7,265
Non-compete agreements
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Useful life	3 years 6 months
Intangible Assets, Gross (Excluding Goodwill)	$ 75	75
Accumulated Amortization	22	18
Intangible Assets, Net	$ 53	$ 57

Finite-Lived and Indefinite-Lived Intangible Assets

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(16))
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482665/350-30-50-2

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- Definition

Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 926
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483154/926-20-50-5

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- Definition

Amount before accumulated amortization of intangible assets, excluding goodwill.

+ References

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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
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