Income Taxes Deferred Tax Assets Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Net operating loss carry-forwards	$ 7,209	$ 6,300
Tax credit carry-forwards	1,888	1,154
Accruals for compensation	8,240	7,160
Accruals for inventory capitalization	1,788	1,813
Unrealized benefit from corporate restructuring	56,985
Unrealized benefit plan loss	3,740	3,417
Unrealized foreign exchange	3,842	7,542
Unearned revenue	1,849	2,760
Other	1,839	822
Total deferred tax assets	87,380	30,968
Valuation allowance	(6,241)	(9,732)	$ (8,200)
Net deferred tax assets	81,139	21,236
Deferred tax liabilities:
Intangibles	(6,263)	(6,025)
Property, plant and equipment	(3,546)	(2,835)
Accrued interest	(1,679)	(3,260)
Accrued withholding taxes	(26,718)	(886)
Unrealized foreign exchange	(2,653)	(4,043)
Other	(306)	(569)
Total deferred tax liabilities	(41,165)	(17,618)
Net deferred income taxes	39,974	3,618
DEFERRED TAX ASSETS, net	67,312	11,252
Long-term deferred tax liabilities	(27,338)	(7,634)
Total deferred tax assets (liabilities)	$ 39,974	$ 3,618