Notes Payable - Long-term debt (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Jan. 31, 2020	Apr. 30, 2019
Long-term Debt
Debt Instrument [Line Items]
Subtotal	$ 929,504	$ 427,860	$ 447,509
Less: Net debt issuance costs (1)	(6,748)	(7,402)	(9,360)
Debt discount	(21,562)	(22,991)	(27,062)
Current portion of long-term debt	(512)	(673)
Total	900,682	396,794	411,087
Senior secured term loan facility (the "Term Loan")
Debt Instrument [Line Items]
Subtotal	300,000
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]
Debt issuance costs	3,900	4,600	6,400
Revolving credit facility \| Long-term Debt
Debt Instrument [Line Items]
Subtotal	500,000		22,509
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
Unsecured Loan \| Long-term Debt
Debt Instrument [Line Items]
Subtotal	$ 4,504	$ 2,860

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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