Income Taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Line Items]
Cumulative effect of change in accounting principles	$ 4,059
Increase (decrease) in deferred tax asset valuation allowance	5,200	$ (20,400)	$ 1,900
Interest and penalties recognize in income tax expense	37	31	$ 35
Interest and penalties recognized on the balance sheet	400	300
Unrecognized tax benefits that would impact effective tax rate	300	$ 400
India
Income Taxes [Line Items]
Deferred tax liability from undistributed foreign earnings	100
Accumulated Deficit
Income Taxes [Line Items]
Cumulative effect of change in accounting principles	4,531
Accumulated Deficit | Accounting Standards Update 2014-09
Income Taxes [Line Items]
Cumulative effect of change in accounting principles	$ 900