Income Taxes from Continuing Operations - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Line Items]
Income tax benefit due to change in tax rate	$ 26,900
Federal corporate income tax rates	35.00%
Valuation allowance	$ 10,531	$ 9,856	$ 8,800
Unrecognized tax benefits that would impact the effective tax rate	2,800
Unrealized increase in goodwill if realized	22,600
Unrecognized tax benefits, income tax penalties	8,900
Unrecognized tax benefits, interest on income taxes	5,900
Unrecognized tax benefits, income tax penalties accrued	8,900
Unrecognized tax benefits, interest on income taxes accrued	6,000
Federal
Income Tax Disclosure [Line Items]
Net operating loss carry-forwards	3,700
Foreign
Income Tax Disclosure [Line Items]
Net operating loss carry-forwards	21,000
Foreign | Switzerland
Income Tax Disclosure [Line Items]
Net operating loss carry-forwards	400
Indefinite Lived NOL | Foreign
Income Tax Disclosure [Line Items]
Net operating loss carry-forwards	10,900
NOL Expiring Beginning In 2022 | Foreign
Income Tax Disclosure [Line Items]
Net operating loss carry-forwards	$ 10,100