Provision for Income Taxes (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current
U.S. state	$ 1,555,000
Total current	1,555,000
Deferred
U.S. federal	190,000	$ (5,606,000)	$ (5,170,000)
U.S. state	7,002,000	(4,334,000)	(14,461,000)
Total deferred	6,812,000	(9,940,000)	(19,631,000)
Valuation allowance	6,800,000	$ 9,940,000	$ 19,631,000
Net deferred	6
Total	$ 1,561,000