Taxes on Income - Effective Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Loss Carryforwards [Line Items]
Income taxes (benefit) at U.S. federal statutory tax rate	$ (21,431)	$ 12,344	$ 425
State income taxes, net of federal income tax benefit	2,270	342	(94)
Divestitures	0	271	2,269
Meals and entertainment	785	736	761
Changes in taxes previously accrued	(1,339)	23	(489)
Foreign tax rate differences	913	(2,559)	(1,468)
Goodwill impairment	6,359	0	3,485
Recognition of uncertain tax positions	(62)	85	24
Deemed mandatory repatriation	10,406	0	0
Release of deferred tax liability on foreign earnings	(7,051)	0	0
Settlement of escrow arrangement	0	0	(1,115)
Domestic Production Activities deduction	(1,921)	(1,017)	(528)
Incremental U.S. taxes on undistributed foreign earnings	0	0	2,102
Other matters	(1,277)	(1,278)	(245)
Total tax provision	$ 5,005	$ 6,109	$ 9,205
Effective tax rate	(8.20%)	17.30%	757.60%
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Change in the balance of the valuation allowance for deferred tax assets allocated to income tax expense	$ 4,598	$ 1,364	$ (756)
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Change in the balance of the valuation allowance for deferred tax assets allocated to income tax expense	$ 12,755	$ (4,202)	$ 4,834