Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation between the statutory federal income tax rate and the effective income tax rate
Federal statutory income tax rate (as a percent)	21.00%	21.00%	35.00%
State income tax rate, net of federal tax benefit (as a percent)	2.90%	2.80%	1.20%
Derecognition of goodwill	0.50%	0.30%	1.60%
Federal deferred rate change			(65.50%)
Partnership income not subject to tax (as a percent)	(21.40%)	(18.90%)	(42.50%)
Effective income tax rate (as a percent)	3.00%	5.20%	(70.20%)
Current:
Federal	$ 35	$ 162	$ 1,371
State	1,036	2,706	1,011
Foreign		4	4
Total current	1,071	2,872	2,386
Deferred:
Federal	815	1,961	(25,217)
State	(792)	790	(732)
Total deferred	23	2,751	(25,949)
Income Tax Expense (Benefit), Total	$ 1,094	$ 5,623	$ (23,563)