Contingent Liabilities and Commitments - Additional Informattion (Detail) $ in Thousands	Feb. 28, 2021 USD ($)
Tank Replacement Costs
Loss Contingencies [Line Items]
Reserve for replacement program	$ 4,948,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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