Income Taxes - Summary of Income before Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Results Of Operations Income Before Income Taxes [Abstract]
U.S. operations	$ 3,092	$ 3,190	$ 1,978
Non-U.S. operations	57,789	82,019	50,058
Income before income taxes	$ 60,881	$ 85,209	$ 52,036