Income Taxes - Deferred Tax Assets Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Tax effects of temporary differences:
Investment in partnership	$ 53,303	$ 41,658
Fixed Assets	29	41
Net operating loss carryforwards and tax credits	6,775	2,538
Other accruals and reversals	5	2
Subtotal	60,112	44,239
Less: valuation allowance	(143)	(206)
Total net deferred tax assets	59,969	44,033
Intangible assets	(293)	(350)
Other	(5)	(5)
Total deferred tax liabilities	$ (298)	$ (355)