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Investments - Contractual Maturities of Debt Securities and Other Investments (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, Fair Value/Carrying Value	$ 29,272	$ 30,066
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	621
One to two years	6,484
Two to three years	3,339
Three to five years	125
Available-for-sale debt securities, Fair Value/Carrying Value	10,569	10,747
Municipal Fixed-Rate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	148
One to two years	1,254
Two to three years	112
Available-for-sale debt securities, Fair Value/Carrying Value	1,514	1,551
Asset-Backed Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Two to three years	248
Three to five years	313
Five to ten years	215
More than ten years	227
Available-for-sale debt securities, Fair Value/Carrying Value	1,003	322
Mortgage/Agency-Backed Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	637
One to two years	472
Two to three years	621
Three to five years	189
Five to ten years	925
More than ten years	1,170
Available-for-sale debt securities, Fair Value/Carrying Value	4,014	4,736
U.S. Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	367
One to two years	8,315
Two to three years	3,102
Available-for-sale debt securities, Fair Value/Carrying Value	11,784	12,171
Foreign Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
One to two years	279
Two to three years	109
Available-for-sale debt securities, Fair Value/Carrying Value	$ 388	$ 539

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Amount of available-for-sale debt securities at fair value maturing after one year through two years.

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+ References

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