Income Taxes - Summary of Tax Effects of Temporary Differences (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Intangible assets	$ 7,352	$ 10,706
Net operating losses	14,750	16,769
Compensation accruals	11,728	7,681
Investments	7,557	7,322
Capital losses	512	870
Other	942	1,675
Gross deferred tax assets	42,841	45,023
Valuation allowance	(8,439)	(3,088)
Gross deferred tax assets after valuation allowance	34,402	41,935
Deferred tax liabilities:
Intangible assets	(12,286)	(9,507)
Gross deferred tax liabilities	(12,286)	(9,507)
Deferred tax assets, net	$ 22,116	$ 32,428