Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Loss Carryforwards [Line Items]
Transition Tax Expense (Benefit), Tax Cuts and Jobs Act of 2017	$ 24,500
Undistributed Earnings of Foreign Subsidiaries	644,200
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 2,000	$ (3,700)
Effective Income Tax Rate Reconciliation, Percent	25.88%	0.80%	1.70%
Income Tax Expense (Benefit)	$ 32,501	$ 777	$ 1,637
Foreign income tax holiday, term	15 years
Foreign	$ 15,212	8,266	3,266
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	1,100		1,029
Reserve for potential uncertain income tax return positions	9,294	9,144	3,265	$ 3,115
Portion of an unrecognized tax benefit netted against deferred tax asset for net operating loss carry forwards	$ 0	341
India
Operating Loss Carryforwards [Line Items]
Foreign income tax holiday, term	5 years
Income Tax Holiday, Aggregate Dollar Amount		$ 4,300	$ 2,900
India | Minimum Alternative Tax (“MAT”)
Operating Loss Carryforwards [Line Items]
Foreign income tax holiday, term	10 years
Maximum | United States
Operating Loss Carryforwards [Line Items]
Income Tax Rate, Tax Cuts and Jobs Act of 2017 Percent	21.00%
Maximum | India
Operating Loss Carryforwards [Line Items]
Foreign tax holiday (percentage)	100.00%
Minimum | India
Operating Loss Carryforwards [Line Items]
Foreign tax holiday (percentage)	50.00%