Change in Estimate (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended			3 Months Ended								12 Months Ended
	Jun. 30, 2016	Feb. 28, 2014	Oct. 31, 2013	Jun. 30, 2016	Mar. 25, 2016	Dec. 25, 2015	Sep. 25, 2015	Jun. 30, 2015	Mar. 27, 2015	Dec. 26, 2014	Sep. 26, 2014	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Gross revenue				$ 169,532	$ 158,130	$ 157,743	$ 135,459	$ 149,087	$ 130,777	$ 143,228	$ 123,025	$ 620,864	$ 546,117	$ 475,677
Net service revenue				132,331	121,253	111,382	100,163	114,567	100,994	99,838	92,619	465,129	408,018	354,956
Insurance recoverables and other income												16,048	6,533	17,874
Segment profit				$ 10,261	$ (23,302)	$ 6,698	$ 7,673	$ 10,703	$ 7,149	$ 6,866	$ 5,992	$ 1,330	$ 30,710	$ 20,921
Diluted earnings (loss) per common share (in dollars per share)				$ 0.19	$ (0.46)	$ 0.13	$ 0.14	$ 0.22	$ 0.17	$ 0.13	$ 0.11	$ 0.00	$ 0.63	$ 0.40
Current Site Remedy [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Modification of Estimate	$ 12,927		$ 12,439									$ 3,983
Insurance recoverables and other income												957
Segment profit												$ 3,026
Diluted earnings (loss) per common share (in dollars per share)												$ 0.06
Current Site Remedy [Member] | Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Gross revenue												$ 3,330	$ 5,093
Net service revenue												9,597	7,346
Insurance recoverables and other income												$ 12,927		$ 12,439
Supplemental Feasibility Study [Member] | Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Modification of Estimate		$ 4,877
Gross revenue													1,855
Net service revenue													$ 3,022
Insurance recoverables and other income														$ 4,877