Fair Value Measurements - Financial Assets and Liabilities Measured and Recorded at Fair Value on a Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Apr. 28, 2019	Jan. 27, 2019
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset	$ 8	$ 69
Total financial assets	3,613	3,174
Derivative financial instruments	18	0
Total financial liabilities	480	2,623
(Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset	0	0
Total financial assets	0	0
Derivative financial instruments	0	0
Total financial liabilities	0	0
(Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset	8	69
Total financial assets	8	69
Derivative financial instruments	18	0
Total financial liabilities	18	0
(Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative Asset	0	0
Total financial assets	3,605	3,105
Derivative financial instruments	0	0
Total financial liabilities	462	2,623
Convertible debt
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale securities	3,605	3,105
Convertible debt | (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale securities	0	0
Convertible debt | (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale securities	0	0
Convertible debt | (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Available-for-sale securities	3,605	3,105
AptoVision
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Earn-out liability	0	2,161
AptoVision | (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Earn-out liability	0	0
AptoVision | (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Earn-out liability	0	0
AptoVision | (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Earn-out liability	0	2,161
Cycleo
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Earn-out liability	462	462
Cycleo | (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Earn-out liability	0	0
Cycleo | (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Earn-out liability	0	0
Cycleo | (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Earn-out liability	$ 462	$ 462