Basis of Presentation and Summary of Significant Accounting Policies Basis of Presentation and Summary of Significant Accounting Policies - Deferred Commissions (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2019	Jan. 31, 2018
Accounting Policies [Abstract]
Beginning balance	$ 87,313	$ 59,394
Additions	131,084	121,752
Recognition of deferred commissions	(103,424)	(93,833)
Ending balance	$ 114,973	$ 87,313

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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Period Type:	instant