Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Operating Revenues:
Total revenues	$ 66,293	$ 74,775	$ 131,778	$ 133,679
Operating Expenses:
Compensation and benefits	21,300	19,301	42,601	38,133
Fund management and administration	15,576	14,621	30,742	25,533
Marketing and advertising	2,910	3,778	5,590	6,973
Sales and business development	4,171	4,503	8,593	8,316
Contractual gold payments (Note 11)	3,110	2,715	6,208	2,715
Professional and consulting fees	1,296	1,560	2,778	3,196
Occupancy, communications and equipment	1,548	1,574	3,166	2,937
Depreciation and amortization	264	337	533	692
Third-party distribution fees	1,919	1,666	4,319	3,391
Acquisition-related costs (Note 3)	33	7,928	346	9,990
Other	2,255	2,261	4,308	4,051
Total expenses	54,382	60,244	109,184	105,927
Operating income	11,911	14,531	22,594	27,752
Other Income/(Expenses):
Interest expense	(2,910)	(2,356)	(5,802)	(2,356)
(Loss)/gain on revaluation of deferred consideration – gold payments (Note 11)	(4,037)	9,898	367	9,898
Interest income	818	612	1,597	1,574
Impairment (Note 14)			(572)
Other gains and losses, net	284	(501)	(4,343)	(762)
Income before income taxes	6,066	22,184	13,841	36,106
Income tax expense	3,587	5,460	2,538	9,958
Net income	$ 2,479	$ 16,724	$ 11,303	$ 26,148
Earnings per share—basic	$ 0.01	$ 0.10	$ 0.07	$ 0.17
Earnings per share—diluted	$ 0.01	$ 0.10	$ 0.07	$ 0.17
Weighted-average common shares—basic	151,818	149,056	151,722	142,230
Weighted-average common shares—diluted	167,249	163,346	166,855	149,979
Cash dividends declared per common share	$ 0.03	$ 0.03	$ 0.06	$ 0.06
Advisory Fees [Member]
Operating Revenues:
Total revenues	$ 65,627	$ 73,778	$ 130,467	$ 132,234
Other Income [Member]
Operating Revenues:
Total revenues	$ 666	$ 997	$ 1,311	$ 1,445