INCOME TAXES - Reconciliation of the beginning and ending amounts of gross unrecognized tax benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at February 1,	$ 82	$ 1,094	$ 1,094
Additions based on tax positions related to the current year	0	0	0
Additions for tax positions of prior years	0	0	0
Reductions for tax positions of prior years	0	0	0
Settlements	0	0	0
Lapses of statutes of limitations	$ (82)	(1,012)	0
Balance at January 31,		$ 82	$ 1,094