Provision for Income Taxes Reconciled to Amount Computed by Applying Statutory Federal Tax Rate to Loss before Income Taxes from Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Tax Expense Benefit Continuing Operations Income Tax Reconciliation [Abstract]
Income tax provision at statutory federal tax rate of 21%	$ (1,057)	$ (173)
State taxes, net of federal benefit	(12)	23
Foreign taxes provisions provided for at rates other than U.S statutory rate	(202)	(486)
Section 951(A) inclusion		108
Expiration of capital loss carryforwards		(689)
Change in valuation allowance	1,432	1,668
Permanent differences	(76)	(135)
Acquisition costs	2	10
Other	(14)
Total provision for income taxes	$ 73	$ 326