Goodwill and Other Intangible Assets - Goodwill (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				0 Months Ended
	Sep. 26, 2014	Sep. 26, 2014 Energy Operating Segment	Sep. 26, 2014 Environmental Operating Segment	Sep. 26, 2014 Infrastructure Operating Segment	Jul. 01, 2014 Covino Environmental Associates, Inc. [Member]	Jul. 01, 2014 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					75
Business Combination, Net Working Capital Adjustment						110
Goodwill [Roll Forward]
Gross Goodwill, Beginning of Period	71,274	27,836	36,214	7,224
Goodwill, Impaired, Accumulated Impairment Loss, Beginning of Period	(39,595)	(14,506)	(17,865)	(7,224)
Goodwill, Beginning of Period	31,679	13,330	18,349	0	992
Goodwill, Period Increase (Decrease)	992	0	992	0
Gross Goodwill, End of Period	72,266	27,836	37,206	7,224
Goodwill, Impaired, Accumulated Impairment Loss, End of Period	(39,595)	(14,506)	(17,865)	(7,224)
Goodwill	$ 32,671	$ 13,330	$ 19,341	$ 0