Taxes on Income - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Statutory income tax rate (as percent)	21.00%	35.00%
Operating Loss Carryforwards [Line Items]
Provisional income tax expense (benefit)	$ (1,900)	$ 2,400
Transition tax for accumulated foreign earnings, provisional liability	9,600	10,400
Deferred tax liability, provisional income tax benefit	7,100	7,100
Provisional income tax expense (benefit), other	2,000	900
Provisional income tax expense (benefit), net of tax credits		5,200
Net operating loss carryforwards	22,909	23,216
DTA, operating loss carryforward, subject to expiration	14,300
DTA, operating loss carryforward, not subject to expiration	8,600
Foreign tax credit carryforwards	507	466
DTA. foreign tax credit carryforwards, subject to expiration	400
Valuation allowance	28,451	29,782	$ 15,428	$ 18,897
Transition tax for accumulated foreign earnings, provisional liability		206,700
Unrecognized tax benefits that would impact effective tax rate	400
Income tax penalties and interest expense	200	$ 300	$ 300
Decrease in unrecognized tax benefits is reasonably possible	800
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
DTA, tax credit carryforward, not subject to expiration	$ 100