Segment Reporting - Additional Information (Detail) - USD ($)	3 Months Ended								12 Months Ended
	Jan. 31, 2017	Oct. 31, 2016	Jul. 31, 2016	Apr. 30, 2016	Jan. 31, 2016	Oct. 31, 2015	Jul. 31, 2015	Apr. 30, 2015	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Schedule Of Sales Revenue By Business Segment [Line Items]
Revenues	$ 12,548,000	$ 8,057,000	$ 8,663,000	$ 11,731,000	$ 11,442,000	$ 15,681,000	$ 7,554,000	$ 17,142,000	$ 40,999,000	$ 51,819,000	$ 83,146,000
Reduction in capital expenditures and fixed assets										6,000	192,000
Eliminations [Member]
Schedule Of Sales Revenue By Business Segment [Line Items]
Revenues									$ 62,000	$ 196,000	$ 562,000