Stock-based Compensation (Summary of Stock Option Activity under Service Based Plans) (Details) - Service-based Stock Option - USD ($) $ / shares in Units, $ in Millions		3 Months Ended	9 Months Ended
		Nov. 02, 2019	May 02, 2020	Aug. 03, 2019
Number of Shares
Options outstanding – August 3, 2019 (in shares)		850,400	850,400
Granted (in shares)			275,900
Exercised (in shares)			0
Canceled/Forfeited (in shares)			(430,500)
Options outstanding – February 1, 2020 (in shares)			695,800
Options vested and expected to vest at February 1, 2020 (in shares)	[1]		684,800
Options exercisable at February 1, 2020 (in shares)			380,000.0
Weighted- Average Exercise Price
Options outstanding – August 3, 2019 (in dollars per share)		$ 156.00	$ 156.00
Granted (in dollars per share)			5.12
Exercised (in dollars per share)			0
Canceled/Forfeited (in dollars per share)			179.89
Options outstanding – February 1, 2020 (in dollars per share)			81.40
Options vested and expected to vest at February 1, 2020 (in dollars per share)	[1]		82.49
Options exercisable at February 1, 2020 (in dollars per share)			$ 130.95
Weighted- Average Remaining Contractual Terms
Options outstanding, weighted-average remaining contractual terms		4 years 1 month 6 days	4 years 9 months 18 days
Options vested and expected to vest at February 1, 2020, weighted-average remaining contractual terms	[1]		4 years 9 months 18 days
Options exercisable at February 1, 2020, weighted-average remaining contractual terms			3 years 8 months 12 days
Aggregate Intrinsic Value
Options outstanding, aggregate intrinsic value	[2]		$ 0.0	$ 0.0
Options vested and expected to vest at February 1, 2020, aggregate intrinsic value	[1],[2]		0.0
Options exercisable at February 1, 2020, aggregate intrinsic value	[2]		$ 0.0

[1] The number of options expected to vest takes into consideration estimated expected forfeitures.

[2] The intrinsic value is the amount by which the market price at the end of the period of the underlying share of stock exceeds the exercise price of the stock option.