CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jan. 23, 2021	Jan. 25, 2020	Jan. 23, 2021	Jan. 25, 2020	Jul. 27, 2019
Statement of Stockholders' Equity [Abstract]
Tax of amortization of pension actuarial loss	$ (45)	$ (44)	$ (91)	$ (88)
Tax expense (benefit) associated with other comprehensive loss and income	$ 263	$ 116	$ 570	$ 160
Tax related to adoption of ASU 2016-02					$ 1,385

Amount of cumulative tax effect on beginning retained earnings from change in accounting principle.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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