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Organization and Summary of Significant Accounting Policies (Narrative) (Details) $ in Millions | Jul. 31, 2021 USD ($) State
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Organization And Summary Of Significant Accounting Policies [Line Items] |
Number of states in which entity operates | State | 43
COVID-19 Pandemic [Member] | Prepaid Expenses and Other Current Assets [Member] |
Organization And Summary Of Significant Accounting Policies [Line Items] |
Income tax receivable, COVID-19 | $ | $ 520

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