Income Taxes - Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current
Federal	$ 0	$ 0	$ 0
State and local	0	0	0
Total current income tax expense (benefit)	0	0	0
Deferred
Federal	2,693	1,939	(978)
State and local	20	4	(3)
Total deferred income tax expense (benefit)	2,713	1,943	(981)
Total income tax expense (benefit)	$ 2,713	$ 1,943	$ (981)