Income Taxes (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Line Items]
Tax Cuts And Jobs Act of 2017, Impact Including Lower Tax Rate, On U.S. Income Tax Expense	$ 2,500	$ 52,100
Provisional charge from net deferred tax assets and liabilities revaluation		48,700
Effective Income Tax Rate Reconciliation, Tax Cuts And Jobs Act Of 2017, Amount	(15,409)	48,680	$ 0
Foreign earnings before tax	88,129	89,757	20,468
Provisional tax expense on outside basis difference		6,500
Differences on international earnings and remittances	5,400	700
Total international income tax expense		31,700
Provisional tax expense from revaluing the U.S. ending net deferred tax assets		14,900
Operating loss carryforwards	83,168	90,193
Capital loss carryforwards	9,759	11,011
Valuation Allowance	138,862	174,227
Valuation allowance related to foreign tax credit carryfowards	15,200	27,300
Deferred Tax Assets, Valuation Allowance, Decrease Due to Altek Acquisition	13,600
Increase from foreign currency translation	8,700	10,100
Net increase related to losses in jurisdictions where the asset will not be recognized		6,900
Tax Cuts and Jobs Act of 2017, Accumulated Foreign Earnings and Profits Indefinitely Reinvested	677,000
Tax Cuts and Jobs Act of 2017, Deferred Foreign Income From Foreign Deficits in Earnings And Profits That Remain Untaxed	49,000	628,000
Tax Cuts and Jobs Act of 2017, GILTI That Increased Earnings Previously Taxed	4,000
Interest and penalties recognized	200	1,700
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	900	1,100	$ 1,100
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	100
Valuation allowance adjustment related to the acquisition of Altek	8,300
Tax Year 2021 [Domain]
Income Tax Disclosure [Line Items]
Capital loss carryforwards	9,800
International operations
Income Tax Disclosure [Line Items]
Operating loss carryforwards	68,100
Operating loss carryforwards not subject to expiration	56,600
Operating losses subject to expiration	11,500
U.S. state
Income Tax Disclosure [Line Items]
Operating loss carryforwards	15,100
U.S. state | Tax Years 2019 through 2023 [Member] [Domain]
Income Tax Disclosure [Line Items]
Operating loss carryforwards	4,300
U.S. state | Tax Years 2024 Through 2028 [Member] [Domain]
Income Tax Disclosure [Line Items]
Operating loss carryforwards	2,900
U.S. state | Tax Years 2029 Through 2033 [Member] [Domain]
Income Tax Disclosure [Line Items]
Operating loss carryforwards	3,400
U.S. state | Expiring between 2028 and 2032
Income Tax Disclosure [Line Items]
Operating loss carryforwards	4,500
United States
Income Tax Disclosure [Line Items]
Differences on international earnings and remittances	$ 3,100	$ 6,400