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Investments - Contractual Maturities of Debt Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Jan. 01, 2020
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, Fair Value/Carrying Value	$ 30,066	$ 45,116	$ 37,700
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	681
One to two years	4,902
Two to three years	4,333
Three to five years	831
Available-for-sale debt securities, Fair Value/Carrying Value	10,747	11,885
Municipal Fixed-Rate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	150
One to two years	1,018
Two to three years	265
Three to five years	118
Available-for-sale debt securities, Fair Value/Carrying Value	1,551	2,884
Asset-Backed Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Two to three years	29
More than ten years	293
Available-for-sale debt securities, Fair Value/Carrying Value	322	6,708
Mortgage/Agency-Backed Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	801
One to two years	868
Three to five years	324
Five to ten years	1,125
More than ten years	1,618
Available-for-sale debt securities, Fair Value/Carrying Value	4,736	11,644
U.S. Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than one year	1,884
One to two years	5,320
Two to three years	4,421
Three to five years	546
Available-for-sale debt securities, Fair Value/Carrying Value	12,171	9,875
Foreign Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
One to two years	245
Two to three years	294
Available-for-sale debt securities, Fair Value/Carrying Value	$ 539	$ 1,337

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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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Amount of available-for-sale debt securities at fair value maturing after three years through five years.

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