Operating Segments - Financial Information for Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2016	Jul. 31, 2015
Segment Reporting Information [Line Items]
Revenues	$ 159,049	$ 176,317	$ 318,788	$ 350,588
(Loss) income from continuing operations before income taxes	(6,051)	(26,503)	(13,641)	(32,316)
Interest expense	4,209	4,295	8,455	8,147
Depreciation expense and amortization	6,954	8,254	13,382	16,989
Non-cash equity-based compensation	845	703	2,092	2,313
Equity in (earnings) losses of affiliates	(458)	1,486	(1,727)	1,593
Impairment charges		4,598		4,598
Restructuring costs	1,005	11,924	1,460	12,114
Gain on extinguishment of debt				4,236
Other expense (income), net	(188)	(252)	(338)	(1,293)
Dividends received from affiliates	1,347	847	2,438	2,210
Adjusted EBITDA	7,663	5,352	12,121	10,119
Operating Segments [Member] | Water Resources [Member]
Segment Reporting Information [Line Items]
Revenues	56,471	60,599	118,421	118,751
(Loss) income from continuing operations before income taxes	(2,238)	(962)	(1,938)	1,929
Depreciation expense and amortization	3,015	3,311	6,168	6,761
Non-cash equity-based compensation	105	80	309	229
Impairment charges		4,598		4,598
Restructuring costs	603	(45)	603	18
Other expense (income), net	280	269	720	(167)
Adjusted EBITDA	1,765	7,251	5,862	13,368
Operating Segments [Member] | Inliner [Member]
Segment Reporting Information [Line Items]
Revenues	52,976	41,790	100,510	89,810
(Loss) income from continuing operations before income taxes	6,808	4,422	12,453	9,664
Depreciation expense and amortization	1,262	1,031	2,516	2,028
Non-cash equity-based compensation	43	46	294	585
Restructuring costs	72	(2)	72	17
Other expense (income), net	(52)	(46)	16	(42)
Adjusted EBITDA	8,133	5,451	15,351	12,252
Operating Segments [Member] | Heavy Civil [Member]
Segment Reporting Information [Line Items]
Revenues	35,414	48,546	74,507	93,629
(Loss) income from continuing operations before income taxes	103	(1,178)	(679)	(3,201)
Depreciation expense and amortization	428	655	897	1,350
Non-cash equity-based compensation	37	5	74	183
Restructuring costs	4	(10)	395	31
Other expense (income), net	(154)	(179)	(138)	(540)
Adjusted EBITDA	418	(707)	549	(2,177)
Operating Segments [Member] | Mineral Services [Member]
Segment Reporting Information [Line Items]
Revenues	14,318	25,981	25,573	49,505
(Loss) income from continuing operations before income taxes	1,634	(14,422)	1,287	(16,974)
Depreciation expense and amortization	1,801	2,788	3,020	5,889
Non-cash equity-based compensation	45	45	94	168
Equity in (earnings) losses of affiliates	(458)	1,486	(1,727)	1,593
Restructuring costs	173	11,675	237	11,696
Other expense (income), net	(479)	(191)	(1,235)	(541)
Dividends received from affiliates	1,347	847	2,438	2,210
Adjusted EBITDA	4,063	2,228	4,114	4,041
Unallocated Corporate Expenses [Member]
Segment Reporting Information [Line Items]
(Loss) income from continuing operations before income taxes	(8,149)	(10,068)	(16,309)	(19,823)
Depreciation expense and amortization	448	469	781	961
Non-cash equity-based compensation	615	527	1,321	1,148
Restructuring costs	153	306	153	352
Other expense (income), net	217	(105)	299	(3)
Adjusted EBITDA	(6,716)	(8,871)	(13,755)	(17,365)
Other Items/ Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(130)	(599)	(223)	(1,107)
(Loss) income from continuing operations before income taxes	(4,209)	(4,295)	(8,455)	(3,911)
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Interest expense	$ 4,209	$ 4,295	$ 8,455	8,147
Gain on extinguishment of debt				$ (4,236)