Summary of Outstanding Borrowings and Borrowing Capacities (Parenthetical) (Detail) $ in Thousands	Sep. 30, 2021 USD ($)
Debt Disclosure [Abstract]
Bonds payable exclude an unamortized discount	$ 648
Prepaid debt issuance costs	$ 35,954

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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