Income Taxes - Summary of Income before Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Results Of Operations Income Before Income Taxes [Abstract]
U.S. operations	$ 2,683	$ 3,092	$ 3,190
Non-U.S. operations	23,046	57,789	82,019
Income before income taxes	$ 25,729	$ 60,881	$ 85,209