Goodwill and Other Intangible Assets - Goodwill (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended		0 Months Ended
	Mar. 27, 2015	Mar. 28, 2014	Mar. 27, 2015	Mar. 28, 2014	Sep. 29, 2014	Jul. 01, 2014	Dec. 26, 2014
Goodwill [Line Items]
Amortization of Intangible Assets	$ 905	$ 755	$ 2,633	$ 2,127
Goodwill [Roll Forward]
Gross Goodwill, Beginning of Period			71,274			71,274
Goodwill, Impaired, Accumulated Impairment Loss, Beginning of Period			(39,595)			(39,595)
Goodwill, Beginning of Period			31,679			31,679
Goodwill, Period Increase (Decrease)			4,675
Gross Goodwill, End of Period	75,949		75,949
Goodwill, Impaired, Accumulated Impairment Loss, End of Period	(39,595)		(39,595)
Goodwill	36,354		36,354
Energy Operating Segment
Goodwill [Roll Forward]
Gross Goodwill, Beginning of Period			27,836			27,836
Goodwill, Impaired, Accumulated Impairment Loss, Beginning of Period			(14,506)			(14,506)
Goodwill, Beginning of Period			13,330			13,330
Goodwill, Period Increase (Decrease)			0
Gross Goodwill, End of Period	27,836		27,836
Goodwill, Impaired, Accumulated Impairment Loss, End of Period	(14,506)		(14,506)
Goodwill	13,330		13,330
Environmental Operating Segment
Goodwill [Roll Forward]
Gross Goodwill, Beginning of Period			36,214			36,214
Goodwill, Impaired, Accumulated Impairment Loss, Beginning of Period			(17,865)			(17,865)
Goodwill, Beginning of Period			18,349			18,349
Goodwill, Period Increase (Decrease)			4,675
Gross Goodwill, End of Period	40,889		40,889
Goodwill, Impaired, Accumulated Impairment Loss, End of Period	(17,865)		(17,865)
Goodwill	23,024		23,024
Infrastructure Operating Segment
Goodwill [Roll Forward]
Gross Goodwill, Beginning of Period			7,224			7,224
Goodwill, Impaired, Accumulated Impairment Loss, Beginning of Period			(7,224)			(7,224)
Goodwill, Beginning of Period			0			0
Goodwill, Period Increase (Decrease)			0
Gross Goodwill, End of Period	7,224		7,224
Goodwill, Impaired, Accumulated Impairment Loss, End of Period	(7,224)		(7,224)
Goodwill	0		0
NOVA Safety & Environmental [Member]
Goodwill [Line Items]
Business Acquisition, Cash Paid					7,198
Business Acquisition, Cost Of Acquired Entity, Cash Paid in Year Two					2,600
Business Acquisition, Intangible Assets Other than Goodwill							3,622
Additions for fiscal year 2015 acquisitions					1,500		287
Business Combination, Net Working Capital Adjustment					560
Goodwill [Roll Forward]
Goodwill, Beginning of Period							3,683
Goodwill							3,683
Business Acquisition, Cost Of Acquired Entity, Cash Paid in Year Two, Due in Period One					508
Business Acquisition, Cost Of Acquired Entity, Cash Paid in Year Two, Due in Period Two					2,092
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares					50
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable					323
Covino Environmental Associates, Inc. [Member]
Goodwill [Line Items]
Business Acquisition, Purchase Price						1,994
Business Acquisition, Cash Paid						1,500
Business Acquisition, Cost Of Acquired Entity, Cash Paid in Year Two						309
Business Acquisition, Intangible Assets Other than Goodwill						601
Additions for fiscal year 2015 acquisitions						75
Business Combination, Net Working Capital Adjustment						110
Goodwill [Roll Forward]
Goodwill, Beginning of Period			$ 992			$ 992