Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2020	Dec. 31, 2021
Income Taxes
Deferred tax assets, operating loss carryforwards	$ 4,547,000		$ 5,070,000
Credit carry-forwards	10,467,000		19,665,000
Deferred tax asset valuation allowance	8,386,000		9,489,000
Foreign tax credit carry-forwards	362,000
Research and development credits	8,082,000
Unrecognized tax benefits	2,079,000
Anticipated reduction in unrecognized tax benefits in next 12 months	222,000
Accrued for interest and penalties related to uncertain income tax	$ 39,000		$ 39,000
Tax years subject to examination	2019 through 2021
Nondeductible for US Tax purposes	$ 6,803,000
Disproportionate tax effect related to pension plan		$ 5,375,000
Earliest Tax Year
Income Taxes
Open tax year	2013
Latest Tax Year
Income Taxes
Open tax year	2021
Operating Loss Carryforward | Minimum
Income Taxes
Tax credit carryforward, expiration year	2023
Operating Loss Carryforward | Maximum
Income Taxes
Tax credit carryforward, expiration year	2042
Foreign Tax Credit Carryforward
Income Taxes
Valuation allowance against tax credit carryforwards	$ 172,000
Foreign Tax Credit Carryforward | Minimum
Income Taxes
Tax credit carryforward, expiration year	2028
Foreign Tax Credit Carryforward | Maximum
Income Taxes
Tax credit carryforward, expiration year	2032
Research Tax Credit Carryforward
Income Taxes
Valuation allowance against tax credit carryforwards	$ 0
Research Tax Credit Carryforward | Minimum
Income Taxes
Tax credit carryforward, expiration year	2023
Research Tax Credit Carryforward | Maximum
Income Taxes
Tax credit carryforward, expiration year	2042