Major Customers - Additional Information (Detail) (Power Industry Services [Member], Customer Concentration Risk [Member])	3 Months Ended		0 Months Ended
	Apr. 30, 2015 Customer	Apr. 30, 2014 Customer	Apr. 30, 2015 Customer	Jan. 31, 2015
Revenue, Major Customer [Line Items]
Number of major power industry service customers	2	3
Revenue [Member]
Revenue, Major Customer [Line Items]
Percentage of consolidated net revenue accounted by major customers	97.00%	97.00%
Accounts Receivable [Member]
Revenue, Major Customer [Line Items]
Number of major power industry service customers			2
Major Customer One [Member] | Revenue [Member]
Revenue, Major Customer [Line Items]
Percentage of consolidated net revenue accounted by major customers	47.00%	38.00%
Major Customer One [Member] | Accounts Receivable [Member]
Revenue, Major Customer [Line Items]
Percentage of consolidated accounts receivable accounted by major customer			44.00%	50.00%
Major Customer Two [Member] | Revenue [Member]
Revenue, Major Customer [Line Items]
Percentage of consolidated net revenue accounted by major customers	45.00%	35.00%
Major Customer Two [Member] | Accounts Receivable [Member]
Revenue, Major Customer [Line Items]
Percentage of consolidated accounts receivable accounted by major customer			43.00%	45.00%
Major Customer Three [Member] | Revenue [Member]
Revenue, Major Customer [Line Items]
Percentage of consolidated net revenue accounted by major customers		23.00%