FAIR VALUE MEASUREMENTS - CONTINGENT CONSIDERATION TABLE (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Changes in the estimated fair value of liability for contingent consideration measured using significant unobservable inputs (Level 3)
Change in fair value, recorded in operating expenses	$ 8,300	$ (7,300)	$ 900
Payments of contingent consideration	(9,400)	(3,300)	(7,400)
Liability for contingent consideration
Changes in the estimated fair value of liability for contingent consideration measured using significant unobservable inputs (Level 3)
Fair value measurement at the beginning of the period	52,733	22,391
Contingent consideration liabilities recorded for business combinations	27,604	26,400
Change in fair value, recorded in operating expenses	(8,324)	7,255
Payments of contingent consideration	(9,412)	(3,313)
Foreign currency translation and other	(228)	0
Fair value measurement at the end of the period	$ 62,829	$ 52,733	$ 22,391
Liability for contingent consideration \| Minimum
Changes in the estimated fair value of liability for contingent consideration measured using significant unobservable inputs (Level 3)
Discount rates (as a percent)	3.00%	3.00%
Liability for contingent consideration \| Maximum
Changes in the estimated fair value of liability for contingent consideration measured using significant unobservable inputs (Level 3)
Discount rates (as a percent)	5.00%	20.00%

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of cumulative translation gain (loss), before tax, from translating foreign currency financial statements into the reporting currency.

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