Investments - Additional Information (Detail) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2022	Sep. 30, 2021
Schedule of Investments [Line Items]
Available-for-sale debt securities, allowance for credit losses	$ 0	$ 0	$ 0
Purchase an available-for-sale debt securities with credit deterioration		0
Asset impairments	$ 16,969,000	$ 16,969,000
Investment [Member] \| Issuer Concentration [Member] \| Market Value of Total Investment Portfolio [Member]
Schedule of Investments [Line Items]
Investment concentration risk percentage		5.00%

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of allowance for credit loss on 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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