Income Taxes - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Income Tax Examination [Line Items]
Income tax expense	$ 73	$ 23	$ 81	$ 47
Effective income tax rate reconciliation, percent	1.86%	0.18%	0.64%	0.26%
Operating loss carryforwards					$ 45,100
Not Subject to Limitations | Subsequent To Change Date In 2010
Income Tax Examination [Line Items]
Operating loss carryforwards					26,500
Subject to Limitations | Minimum
Income Tax Examination [Line Items]
Operating loss carryforwards					1,000
Subject to Limitations | Maximum
Income Tax Examination [Line Items]
Operating loss carryforwards					$ 2,300