Stock-Based Compensation - Restricted Stock (Details)	12 Months Ended
	Jan. 25, 2020 $ / shares shares
Number of Shares
Nonvested, beginning of year (in shares) | shares	314,027
Granted (in shares) | shares	628,485
Vested (in shares) | shares	(98,665)
Forfeited (in shares) | shares	(95,335)
Nonvested, end of year (in shares) | shares	748,512
Weighted Average Grant Date Fair Value
Nonvested, beginning of year (in dollars per share) | $ / shares	$ 29.39
Granted (in dollars per share) | $ / shares	10.80
Vested (in dollars per share) | $ / shares	29.58
Forfeited (in dollars per share) | $ / shares	20.38
Nonvested, end of year (in dollars per share) | $ / shares	$ 14.90
RSUs | Minimum
Vesting period (in years)	1 year
RSUs | Maximum
Vesting period (in years)	4 years