Business Description and Summary of Significant Accounting Policies - Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Business Description and Summary of Significant Accounting Policies
Income tax expense	$ (521)	$ 238	$ 240	$ 409
Income Tax Expense (% Change)			(41.30%)
Effective tax rate			18.20%	17.40%
Effective tax rate (% Change)			0.80%