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Investments - Contractual Maturities of Debt Securities and Other Investments (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, Fair Value/Carrying Value	$ 28,663	$ 30,066
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	96
One to two years	5,371
Two to three years	3,517
Available-for-sale debt securities, Fair Value/Carrying Value	8,984	10,747
Municipal Fixed-Rate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	525
One to two years	722
Two to three years	110
Available-for-sale debt securities, Fair Value/Carrying Value	1,357	1,551
Asset-Backed Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
One to two years	95
Two to three years	715
Three to five years	1,306
Five to ten years	382
More than ten years	413
Available-for-sale debt securities, Fair Value/Carrying Value	2,911	322
Mortgage/Agency-Backed Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	182
One to two years	464
Two to three years	1,321
Three to five years	166
Five to ten years	810
More than ten years	1,497
Available-for-sale debt securities, Fair Value/Carrying Value	4,440	4,736
U.S. Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
One to two years	7,421
Two to three years	2,889
Three to five years	279
Available-for-sale debt securities, Fair Value/Carrying Value	10,589	12,171
Foreign Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
One to two years	275
Two to three years	107
Available-for-sale debt securities, Fair Value/Carrying Value	$ 382	$ 539

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