Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Examination [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Domestic	$ (31,061)	$ (37,696)	$ (16,027)
Income (Loss) from Continuing Operations before Income Taxes, Foreign	39,753	23,018	(2,840)
Income before income tax	8,692	(14,678)	(18,867)
Valuation Allowance, Deferred Tax Asset, Change in Amount	10,400	800	3,700
Valuation Allowance, Amount	62,739	52,380	$ 51,558
Excess Tax Benefit Deduction from Share-based Compensation, Operating Activities	41,600
Excess Tax Benefit (Tax Deficiency) from Share-based Compensation, Operating Activities	$ 15,200
Excess tax benefit related to stock options		$ 9,900
State And Federal Operating Loss Carryforwards, Beginning Expiration Dates	Dec. 31, 2019
State And Federal Operating Loss Carryforwards, Ending Expiration Dates	Dec. 31, 2037
Pre-2006 Windfall Stock Option Deduction Valuation Allowance [Member]
Income Tax Examination [Line Items]
Valuation Allowance, Amount	$ 4,500
Domestic Tax Authority [Member]
Income Tax Examination [Line Items]
Operating Loss Carryforwards	80,000
Deferred Tax Assets, Tax Credit Carryforwards, Research	6,500
State and Local Jurisdiction [Member]
Income Tax Examination [Line Items]
Operating Loss Carryforwards	26,000
Deferred Tax Assets, Tax Credit Carryforwards, Research	$ 14,500
Internal Revenue Service (IRS) [Member] | Domestic Tax Authority [Member]
Income Tax Examination [Line Items]
Federal statutory rate (percent)	35.00%
Minimum [Member]
Income Tax Examination [Line Items]
Federal Tax Credit Carryforwards, Ending Expiration Dates	Dec. 31, 2021
Maximum [Member]
Income Tax Examination [Line Items]
Federal Tax Credit Carryforwards, Ending Expiration Dates	Dec. 31, 2035