Income Taxes - Schedule of Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Pension and other retiree obligations	$ 323	$ 91
Inventory	482	438
Other accruals and reserves	5,020	4,580
Loss and credit carryforwards	39,172	32,020
Interest expense deduction limitation carryforward	8,147	7,767
Investments	2,137	2,170
Right-of-use asset	1,410	1,505
Other	2,326	0
Valuation allowance	(55,996)	(19,587)
Deferred tax assets	3,021	28,984
Deferred tax liabilities:
Intangible assets other than goodwill	(24,404)	(23,953)
Property, plant and equipment	(1,315)	(1,964)
Unrealized foreign currency gains	(3,862)	0
Lease liability	(1,575)	(1,571)
Other	0	(396)
Deferred tax liabilities	(31,156)	(27,884)
Net deferred tax (liabilities) assets	$ (28,135)
Deferred Tax Assets, Net		$ 1,100