Income Taxes - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) installment
Schedule Of Income Taxes [Line Items]
Income (loss) of foreign subsidiaries before taxes	$ 22,000	$ 165,000
Deferred tax valuation allowance against assets	3,200,000		$ 3,200,000
Income tax expense	6,000	$ 5,000
Federal tax liability	2,200,000		$ 2,200,000
Federal tax liability payableperiod			8 years
Percentage of federal tax liability payable in first five installments			8.00%
Percentage of federal tax liability payable in sixth installment			15.00%
Percentage of federal tax liability payable in seventh installment			20.00%
Percentage of federal tax liability payable in final installment			25.00%
Number of installments for federal tax liability payable | installment			8
Number of installments of federal tax liability paid | installment			2
U.S. federal
Schedule Of Income Taxes [Line Items]
Net operating loss carry forwards, amount	8,700,000		$ 8,700,000
Operating loss carryovers, limitations on use			At June 30, 2020, the Company had $8.7 million of U.S. federal net operating loss (“NOL”) carry forwards. These losses do not expire but are limited to utilization of 80% of taxable income in any one year.
Percentage of NOLs utilization limit against taxable income			80.00%
U.S. federal | Earliest Tax Year
Schedule Of Income Taxes [Line Items]
Open tax years			2016
U.S. federal | Latest Tax Year
Schedule Of Income Taxes [Line Items]
Open tax years			2019
States
Schedule Of Income Taxes [Line Items]
Net operating loss carry forwards, amount	$ 16,600,000		$ 16,600,000
States | Earliest Tax Year
Schedule Of Income Taxes [Line Items]
Open tax years			2015
States | Latest Tax Year
Schedule Of Income Taxes [Line Items]
Open tax years			2019