Income Taxes - Components of benefit for income taxes (Details) - USD ($) $ in Thousands	3 Months Ended					12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current income tax provision (benefit)
Federal						$ 49	$ (25)	$ 75
State						61	7	10
Total current income tax provision (benefit)						110	(18)	85
Deferred income tax (benefit) provision
Federal						(295)	(167)	(58)
State						(69)	(211)	(50)
Total deferred income tax (benefit)						(364)	(378)	(108)
Total benefit from income taxes	$ (138)	$ (331)	$ 135	$ 80	$ (396)	$ (254)	$ (396)	$ (23)