Investments - Summary of Available-for-Sale Securities (Detail) - Failed Auction Security [Member] - USD ($)	Jun. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Cost	$ 3,000,000	$ 3,000,000
Gross Unrealized Losses	416,000	359,000
Estimated Fair Value	$ 2,584,000	$ 2,641,000

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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+ Details

- Definition

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.

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