Investments - Breakdown of Investments with Unrealized Losses (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Continuous Unrealized Loss Position for Less than 12 Months, Fair Value	$ 21,974	$ 3,378
Continuous Unrealized Loss Position for Less than 12 Months, Unrealized Losses	(171)	(7)
Total Fair Value	21,974	3,378
Total Unrealized Losses	(171)	(7)
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Continuous Unrealized Loss Position for Less than 12 Months, Fair Value	6,795	336
Continuous Unrealized Loss Position for Less than 12 Months, Unrealized Losses	(35)
Total Fair Value	6,795	336
Total Unrealized Losses	(35)
Municipal Fixed-Rate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Continuous Unrealized Loss Position for Less than 12 Months, Fair Value	1,129	310
Continuous Unrealized Loss Position for Less than 12 Months, Unrealized Losses	(4)
Total Fair Value	1,129	310
Total Unrealized Losses	(4)
Asset-Backed Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Continuous Unrealized Loss Position for Less than 12 Months, Fair Value	198	2
Continuous Unrealized Loss Position for Less than 12 Months, Unrealized Losses	(3)
Total Fair Value	198	2
Total Unrealized Losses	(3)
Mortgage/Agency-Backed Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Continuous Unrealized Loss Position for Less than 12 Months, Fair Value	3,006	2,078
Continuous Unrealized Loss Position for Less than 12 Months, Unrealized Losses	(33)	(6)
Total Fair Value	3,006	2,078
Total Unrealized Losses	(33)	(6)
U.S. Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Continuous Unrealized Loss Position for Less than 12 Months, Fair Value	10,552	350
Continuous Unrealized Loss Position for Less than 12 Months, Unrealized Losses	(92)
Total Fair Value	10,552	350
Total Unrealized Losses	(92)
Foreign Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Continuous Unrealized Loss Position for Less than 12 Months, Fair Value	294	302
Continuous Unrealized Loss Position for Less than 12 Months, Unrealized Losses	(4)	(1)
Total Fair Value	294	302
Total Unrealized Losses	$ (4)	$ (1)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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