Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Examination [Line Items]
Provision (benefit) for income taxes	$ 971	$ 3,723	$ 2,067	$ 1,041	$ (1,212)	$ (2,214)	$ 1,700	$ 1,179	$ 29,535	$ (3,524)	$ (10,096)	$ (6,943)		$ 7,802	$ (547)	$ 8,972
Tax rate														35.00%	35.00%	35.00%
Tax expense from revalue of deferred tax liabilities														$ 37,889
Income tax expense related to transition tax														9,474
Net tax expense related to transition tax and revaluation of deferred tax balances														47,362
Difference between effective tax rate and federal statutory rate															33.60%	36.40%
Valuation allowance	80,796				109,913									80,796	$ 109,913
Deferred income tax assets	35,004				29,398									35,004	29,398
Net operating loss carryforwards	237,186				148,199									237,186	148,199
Loss carryforwards for U.S. federal income tax purposes	115,846				50,587									115,846	50,587
Loss carryforwards for U.S. state income tax purposes	101,563				78,274									101,563	78,274
Loss carryforwards for foreign income tax purposes	19,777				19,338									19,777	19,338
Unrecognized benefits														218	10,077
Anticipated additional unrecognized tax benefits during the next twelve months														$ 0
Scenario, Plan [Member]
Income Tax Examination [Line Items]
Tax rate													21.00%
Australia Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2013
Belgium Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2014
Brazil Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2012
China Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2014
France Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2014
German Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2013
India Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2013
Israel Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2013
Italy Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2012
Japan Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2012
Korea Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2012
Mexican Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2012
Netherlands Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2012
Switzerland Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2012
United Kingdom Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2016
Uruguay Tax Authority [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2012
Minimum [Member] | U.S. Internal Revenue Service [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2003
Maximum [Member] | U.S. Internal Revenue Service [Member]
Income Tax Examination [Line Items]
Tax years subject to examination														2017
U.S Federal Income Tax [Member]
Income Tax Examination [Line Items]
Difference in effective rate due to Tax Act														48.60%
Research and experimentation tax credit carryforwards	2,845				2,544									$ 2,845	2,544
Foreign tax credits	3,549				7,155									3,549	7,155
Other tax credits	474													$ 474
U.S Federal Income Tax [Member] | Minimum [Member]
Income Tax Examination [Line Items]
Net operating loss carryforwards beginning expiration date														Dec. 31, 2022
U.S. State Income Tax [Member]
Income Tax Examination [Line Items]
Research and experimentation tax credit carryforwards	3,745				2,649									$ 3,745	2,649
Tax credit carryforwards beginning expiration date														Dec. 31, 2017
U.S. State Income Tax [Member] | Minimum [Member]
Income Tax Examination [Line Items]
Net operating loss carryforwards beginning expiration date														Dec. 31, 2017
Foreign Income Tax [Member]
Income Tax Examination [Line Items]
Research and experimentation tax credit carryforwards	170				149									$ 170	149
Foreign Income Tax [Member] | Minimum [Member]
Income Tax Examination [Line Items]
Net operating loss carryforwards beginning expiration date														Dec. 31, 2018
Other State Income Tax [Member]
Income Tax Examination [Line Items]
Other tax credits	$ 600				$ 600									$ 600	$ 600
Tax credit carryforwards beginning expiration date														Dec. 31, 2024