Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2020		Sep. 30, 2019	Sep. 30, 2020		Sep. 30, 2019
Operating Revenues:
Total revenues	$ 64,640		$ 67,718	$ 186,640		$ 199,496
Operating Expenses:
Compensation and benefits	19,098		18,880	53,848		61,481
Fund management and administration	15,219		15,110	44,165		45,852
Marketing and advertising	2,996		3,022	7,413		8,612
Sales and business development	2,386		4,354	7,984		12,947
Contractual gold payments (Note 11)	4,539		3,502	12,362		9,710
Professional and consulting fees	950		1,259	3,580		4,037
Occupancy, communications and equipment	1,611		1,549	4,805		4,715
Depreciation and amortization	253		259	760		792
Third-party distribution fees	1,233		1,503	3,928		5,822
Acquisition and disposition-related costs			190	416		536
Other	1,611		1,959	5,204		6,267
Total operating expenses	49,896		51,587	144,465		160,771
Operating income	14,744		16,131	42,175		38,725
Other Income/(Expenses):
Interest expense	(2,511)		(2,832)	(6,974)		(8,634)
Loss on revaluation of deferred consideration – gold payments (Note 11)	(8,870)		(6,306)	(34,436)		(5,939)
Interest income	111		799	393		2,396
Impairments (Note 26)	(3,080)			(22,752)		(572)
Loss on extinguishment of debt (Note12)				(2,387)
Other gains and losses, net	744		843	56		(3,500)
Income/(loss) before income taxes	1,138		8,635	(23,925)		22,476
Income tax expense/(benefit)	1,408		4,483	(1,767)		7,021
Net (loss)/income	$ (270)		$ 4,152	$ (22,158)		$ 15,455
(Loss)/earnings per share—basic	$ (0.01)		$ 0.02	$ (0.16)		$ 0.09
(Loss)/earnings per share—diluted	$ (0.01)		$ 0.02	$ (0.16)		$ 0.09
Weighted-average common shares—basic	145,564		151,897	149,886		151,782
Weighted-average common shares—diluted	145,564	[1]	167,163	149,886	[1]	166,944
Cash dividends declared per common share	$ 0.03		$ 0.03	$ 0.09		$ 0.09
Advisory Fees [Member]
Operating Revenues:
Total revenues	$ 63,919		$ 67,006	$ 184,077		$ 197,473
Other Income [Member]
Operating Revenues:
Total revenues	$ 721		$ 712	$ 2,563		$ 2,023

[1] Excludes 15,307,153 and 14,997,269 participating securities and 4,669 and 5,437 potentially dilutive non-participating common stock equivalents for the three and nine months ended September 30, 2020 as the Company reported a net loss for the period.