Leases (Details) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Jan. 31, 2020 USD ($)	Jan. 31, 2020 USD ($) Period	Jul. 31, 2009 Store	Jul. 28, 2000 Store	Aug. 02, 2019 USD ($)
Components of Lease Cost for Operating Leases [Abstract]
Operating lease cost	$ 20,462	$ 40,318
Short term lease cost	1,892	2,276
Variable lease cost	479	930
Total lease cost	22,833	43,524
Operating cash flow information [Abstract]
Cash paid for amounts included in the measurement of lease liabilities	20,286	39,832
Noncash information [Abstract]
Right-of-use assets obtained in exchange for new operating lease liabilities	601	4,439
Lease modifications granting additional right-of-use assets	5,691	12,517
Lease modifications removing right-of-use assets	$ (280)	$ (929)
Weighted-Average Remaining Lease Term and Weighted-Average Discount Rate for Operating Leases [Abstract]
Weighted-average remaining lease term	18 years 14 days	18 years 14 days
Weighted-average discount rate	3.86%	3.86%
Maturities of Undiscounted Cash Flows Reconciled to Total Lease Liability [Abstract]
Remainder of 2020	$ 39,873	$ 39,873
2021	50,982	50,982
2022	41,429	41,429
2023	37,390	37,390
2024	36,726	36,726
Thereafter	533,084	533,084
Total future minimum lease payments	739,484	739,484
Less imputed remaining interest	(229,122)	(229,122)
Total present value of operating lease liabilities	$ 510,362	$ 510,362
Maturities of Lease Commitments Prior to Adoption of New Lease Guidance [Abstract]
2020					$ 69,249
2021					40,962
2022					36,280
2023					33,639
2024					34,020
Thereafter					515,169
Total					$ 729,319
Restaurant [Member]
Sale Leaseback Transactions [Abstract]
Initial lease term	10 years	10 years
Lease renewal option	5 years	5 years
Undiscounted future payments for leases not yet commenced	$ 15,900	$ 15,900
Restaurant [Member] | Minimum [Member]
Sale Leaseback Transactions [Abstract]
Number of optional renewal periods | Period		4
Restaurant [Member] | Maximum [Member]
Sale Leaseback Transactions [Abstract]
Number of optional renewal periods | Period		5
Sale-leaseback Transactions in 2009 [Member] | Owned Stores [Member]
Sale Leaseback Transactions [Abstract]
Number of owned stores involved in sale-lease back transactions | Store			15
Initial lease term	20 years	20 years
Lease renewal option	20 years	20 years
Sale-leaseback Transactions in 2009 [Member] | Retail Distribution Center [Member]
Sale Leaseback Transactions [Abstract]
Initial lease term	15 years	15 years
Lease renewal option	20 years	20 years
Sale-leaseback Transactions in 2000 [Member] | Owned Stores [Member]
Sale Leaseback Transactions [Abstract]
Number of owned stores involved in sale-lease back transactions | Store				65
Initial lease term	21 years	21 years
Lease renewal option	20 years	20 years