STOCK-BASED COMPENSATION STOCK-BASED COMPENSATION - STOCK-BASED COMPENSATION - BY LINE ITEM (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 30, 2020	Apr. 30, 2019
Stock-Based Compensation Plans
Stock-based compensation expense	$ 14,184	$ 17,103
Cost of revenue - product
Stock-Based Compensation Plans
Stock-based compensation expense	310	334
Cost of revenue - service and support
Stock-Based Compensation Plans
Stock-based compensation expense	657	1,070
Research and development, net
Stock-Based Compensation Plans
Stock-based compensation expense	2,336	2,590
Selling, General and Administrative Expenses
Stock-Based Compensation Plans
Stock-based compensation expense	$ 10,881	$ 13,109

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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