Description of the Business and Basis of Presentation - Schedule of Net Revenues by Service Category (Detail) (USD $)	3 Months Ended		9 Months Ended
	Oct. 31, 2013	Oct. 31, 2012	Oct. 31, 2013	Oct. 31, 2012
Product Information [Line Items]
Net revenues	$ 63,452,000	$ 74,486,000	$ 167,964,000	$ 220,794,000
Power Industry Services [Member]
Product Information [Line Items]
Net revenues	61,103,000	70,527,000	160,392,000	206,364,000
Core Services [Member] | Power Industry Services [Member]
Product Information [Line Items]
Net revenues	46,858,000	70,527,000	146,147,000	206,364,000
Project Development Services [Member] | Power Industry Services [Member]
Product Information [Line Items]
Net revenues	$ 14,245,000		$ 14,245,000