Operating Segments - Segment Summary (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Mar. 28, 2014	Mar. 29, 2013	Mar. 28, 2014 segment	Mar. 29, 2013
Segment Reporting Information [Line Items]
Sales Revenue, Services, Other	$ 120,836	$ 109,806	$ 350,002	$ 322,562
Number of operating segments (in segments)			3
Net service revenue	88,081	83,044	260,464	233,514
Segment profit	2,511	3,392	11,960	12,397
Depreciation and amortization	2,161	1,828	6,587	4,959
Total [Member]
Segment Reporting Information [Line Items]
Sales Revenue, Services, Other	119,453	108,963	347,434	320,521
Net service revenue	86,974	82,172	257,629	231,501
Segment profit	17,108	15,226	51,449	45,024
Depreciation and amortization	1,574	1,310	4,742	3,330
Energy
Segment Reporting Information [Line Items]
Sales Revenue, Services, Other	44,480	34,505	118,050	98,297
Net service revenue	34,632	29,145	98,339	80,660
Segment profit	7,908	5,185	19,313	16,831
Depreciation and amortization	835	564	2,385	1,257
Environmental
Segment Reporting Information [Line Items]
Sales Revenue, Services, Other	60,750	59,664	182,692	177,203
Net service revenue	41,939	41,423	124,860	118,292
Segment profit	7,787	7,253	25,898	21,987
Depreciation and amortization	633	651	2,039	1,729
Infrastructure
Segment Reporting Information [Line Items]
Sales Revenue, Services, Other	14,223	14,794	46,692	45,021
Net service revenue	10,403	11,604	34,430	32,549
Segment profit	1,413	2,788	6,238	6,206
Depreciation and amortization	$ 106	$ 95	$ 318	$ 344

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

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- Definition

Aggregate revenue during the period for services rendered in the normal course of business (before deducting allowances and discounts) which are not otherwise defined in the taxonomy.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(d))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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Aggregate revenue during the period from services rendered in the normal course of business, after deducting allowances and discounts.

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