Notes Payable - Long-term debt (Details) - USD ($) $ in Thousands	Apr. 30, 2019	Jan. 31, 2019	Apr. 30, 2018
Long-term Debt
Debt Instrument [Line Items]
Subtotal	$ 447,509	$ 425,000	$ 492,377
Less: Net debt issuance costs	(9,360)	(10,014)	(11,974)
Debt discount	(27,062)	(28,382)	(32,140)
Total	411,087	386,604	448,263
Senior secured term loan facility (the "Term Loan") \| Long-term Debt
Debt Instrument [Line Items]
Subtotal	300,000	300,000	300,000
Revolving credit facility
Debt Instrument [Line Items]
Less: Net debt issuance costs	(6,400)	(7,100)	(8,900)
Revolving credit facility \| Long-term Debt
Debt Instrument [Line Items]
Subtotal	22,509		67,377
LVMH Note
Debt Instrument [Line Items]
Debt discount	(40,000)
LVMH Note \| Long-term Debt
Debt Instrument [Line Items]
Subtotal	$ 125,000	$ 125,000	$ 125,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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