CASH, CASH EQUIVALENTS, AND SHORT-TERM INVESTMENTS CASH, CASH EQUIVALENTS, AND SHORT-TERM INVESTMENTS (Tables)

12 Months Ended

Jan. 31, 2018

Cash, Cash Equivalents, and Short-term Investments [Abstract]

Schedule of Cash, Cash Equivalents and Short-term Investments [Table Text Block]

The following tables summarize our cash, cash equivalents, and short-term investments as of January 31, 2018 and 2017:

	January 31, 2018
(in thousands)	Cost Basis		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Cash and cash equivalents:
Cash and bank time deposits	$	337,756	$	—	$	—	$	337,756
Money market funds	186		—		—		186
Total cash and cash equivalents	$	337,942	$	—	$	—	$	337,942
Short-term investments:
Corporate debt securities (available-for-sale)	$	2,002	$	—	$	—	$	2,002
Bank time deposits	4,564		—		—		4,564
Total short-term investments	$	6,566	$	—	$	—	$	6,566

	January 31, 2017
(in thousands)	Cost Basis		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Cash and cash equivalents:
Cash and bank time deposits	$	307,188	$	—	$	—	$	307,188
Money market funds	175		—		—		175
Total cash and cash equivalents	$	307,363	$	—	$	—	$	307,363
Short-term investments:
Bank time deposits	$	3,184	$	—	$	—	$	3,184
Total short-term investments	$	3,184	$	—	$	—	$	3,184