Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Number of shares issued during the period to an employee benefit plan, such as a defined contribution or defined benefit plan.

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Long-Term Incentive Awards (Details) - USD ($)	3 Months Ended					9 Months Ended		12 Months Ended
Long-Term Incentive Awards (Details) - USD ($)	Jan. 25, 2020	Jul. 27, 2019	Jan. 26, 2019	Jul. 28, 2018	Jul. 29, 2017	Jan. 25, 2020	Jan. 26, 2019	Apr. 30, 2019
Stock Based Compensation
Stock based compensation expense						$ 0		$ 0
Fiscal 2020 LTIP \| Performance based restricted stock units
Stock Based Compensation
Stock based compensation expense	$ 215,000					512,000
Exercisable period from grant date		3 years
Fiscal 2020 LTIP \| Performance based restricted stock units \| 100% Vested
Stock Based Compensation
Vesting (as a percentage)		100.00%
Fiscal 2020 LTIP \| Performance based restricted stock units \| 50% Vested
Stock Based Compensation
Vesting (as a percentage)		50.00%
Fiscal 2020 LTIP \| Performance based restricted stock units \| 200% Vested
Stock Based Compensation
Vesting (as a percentage)		200.00%
Fiscal 2020 LTIP \| Performance based restricted stock units \| Maximum
Stock Based Compensation
Stock based compensation expense						4,263,000
Fiscal 2019 LTIP \| Performance based restricted stock units
Stock Based Compensation
Stock based compensation expense	246,000		$ 226,000			294,000	$ 482,000
Exercisable period from grant date				3 years
Fiscal 2019 LTIP \| Performance based restricted stock units \| 100% Vested
Stock Based Compensation
Vesting (as a percentage)				100.00%
Fiscal 2019 LTIP \| Performance based restricted stock units \| 50% Vested
Stock Based Compensation
Vesting (as a percentage)				50.00%
Fiscal 2019 LTIP \| Performance based restricted stock units \| 200% Vested
Stock Based Compensation
Vesting (as a percentage)				200.00%
Fiscal 2019 LTIP \| Performance based restricted stock units \| Maximum
Stock Based Compensation
Stock based compensation expense						2,478,000
Fiscal 2018 LTIP \| Performance based restricted stock units
Stock Based Compensation
Stock based compensation expense	201,000		$ 317,000			162,000	$ 653,000
Exercisable period from grant date					3 years
Fiscal 2018 LTIP \| Performance based restricted stock units \| 100% Vested
Stock Based Compensation
Vesting (as a percentage)					100.00%
Fiscal 2018 LTIP \| Performance based restricted stock units \| 50% Vested
Stock Based Compensation
Vesting (as a percentage)					50.00%
Fiscal 2018 LTIP \| Performance based restricted stock units \| 200% Vested
Stock Based Compensation
Vesting (as a percentage)					200.00%
Fiscal 2018 LTIP \| Performance based restricted stock units \| Maximum
Stock Based Compensation
Stock based compensation expense						1,850,000
Fiscal 2017 LTIP \| Performance based restricted stock units
Stock Based Compensation
Stock based compensation expense	$ 0					0
Exercisable period from grant date					3 years
Issue of fully-vested shares of common stock to settle		14,814
Fiscal 2020 LTIP, Fiscal 2019 LTIP and Fiscal 2018 LTIP
Stock Based Compensation
Stock based compensation expense						$ 2,397,000		$ 1,429,000