Goodwill and Other Intangible Assets - Goodwill (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Mar. 29, 2013	Jan. 18, 2014	Jan. 18, 2013	Dec. 31, 2012
Goodwill [Line Items]
Business Acquisition, Cost of Acquired Entity, Cash Paid			$ 3,150	$ 3,500
Goodwill [Roll Forward]
Goodwill, Gross	64,483
Goodwill, Impaired, Accumulated Impairment Loss	(39,595)
Goodwill	24,888
Goodwill, Period Increase (Decrease)	3,472
Goodwill, Gross	67,955
Goodwill, Impaired, Accumulated Impairment Loss	(39,595)
Goodwill	28,360
Business Acquisition, Purchase Price Allocation, Goodwill Amount			848	2,624
Business Acquisition, Purchase Price Allocation, Intangible Assets Other than Goodwill			1,849	2,618
Business Acquisition, Cost of Acquired Entity, Subordinated Debt Incurred, Excluding Contingent Consideration				1,500
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares		88
Business Acquisition, Cost of Acquired Entity, Equity Interests Issued and Issuable				515
Additions for fiscal year 2013 acquisitions	475			475
Energy Operating Segment
Goodwill [Roll Forward]
Goodwill, Gross	21,893
Goodwill, Impaired, Accumulated Impairment Loss	(14,506)
Goodwill	7,387
Goodwill, Period Increase (Decrease)	2,624
Goodwill, Gross	24,517
Goodwill, Impaired, Accumulated Impairment Loss	(14,506)
Goodwill	10,011
Environmental Operating Segment
Goodwill [Roll Forward]
Goodwill, Gross	35,366
Goodwill, Impaired, Accumulated Impairment Loss	(17,865)
Goodwill	17,501
Goodwill, Period Increase (Decrease)	848
Goodwill, Gross	36,214
Goodwill, Impaired, Accumulated Impairment Loss	(17,865)
Goodwill	18,349
Infrastructure Operating Segment
Goodwill [Roll Forward]
Goodwill, Gross	7,224
Goodwill, Impaired, Accumulated Impairment Loss	(7,224)
Goodwill	0
Goodwill, Period Increase (Decrease)	0
Goodwill, Gross	7,224
Goodwill, Impaired, Accumulated Impairment Loss	(7,224)
Goodwill	$ 0
Subordinated Debt
Goodwill [Roll Forward]
Debt Instrument, Interest Rate, Stated Percentage	3.00%