NOTES PAYABLE AND OTHER LIABILITIES - Accrued expenses (Details) - USD ($) $ in Thousands	Jan. 31, 2019	Jan. 31, 2018
Debt Disclosure [Abstract]
Accrued bonuses	$ 44,519	$ 36,137
Other accrued expenses	58,322	58,918
Accrued Liabilities, Current, Total	$ 102,841	$ 95,055

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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