Components of Income Tax Expenses (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current income tax expense:
Foreign	$ 14	$ 4	$ 54
U.S. Federal	2,207	422	0
Total current income tax expense	2,221	426	54
Deferred income tax expense:
U.S. Federal	5,326	2,395	3,395
Total deferred income tax expense	5,326	2,395	3,395
Total income tax expense	$ 7,547	$ 2,821	$ 3,449