Condensed Consolidated Statements of Operations - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue:
Revenue	$ 178,200,000	$ 196,400,000	$ 527,400,000	$ 609,800,000
Total revenue	182,400,000	197,800,000	539,700,000	612,100,000
Operating expenses:
Impairment of goodwill	0	0	16,400,000	0
Amortization of acquired intangibles	1,600,000	1,600,000	5,100,000	4,900,000
Total operating expenses	141,900,000	145,900,000	398,900,000	445,600,000
Operating income	40,500,000	51,900,000	140,800,000	166,500,000
Non-operating income and (expense):
Gain on sale of Affiliate	7,200,000		7,200,000
Net consolidated Funds’ investment gains	6,000,000.0	7,000,000.0	17,300,000	25,200,000
Total non-operating income (loss)	6,300,000	(900,000)	2,900,000	2,900,000
Income from continuing operations before taxes	46,800,000	51,000,000.0	143,700,000	169,400,000
Income tax expense (benefit)	12,800,000	(32,000,000.0)	33,700,000	3,700,000
Income from continuing operations	34,000,000.0	83,000,000.0	110,000,000.0	165,700,000
Gain (loss) on disposal of discontinued operations, net of tax	0	0	0	0
Net income	34,000,000.0	83,000,000.0	110,000,000.0	165,700,000
Net income (loss) attributable to non-controlling interests in consolidated Funds	(3,200,000)	7,600,000	21,300,000	9,600,000
Net income attributable to controlling interests	$ 37,200,000	$ 75,400,000	$ 88,700,000	$ 156,100,000
Earnings per share (basic) attributable to controlling interests (in dollars per share)	$ 0.46	$ 0.84	$ 1.08	$ 1.68
Earnings per share (diluted) attributable to controlling interests (in dollars per share)	0.46	0.84	1.08	1.68
Continuing operations earnings per share (basic) attributable to controlling interests (in dollars per share)	0.46	0.84	1.08	1.68
Continuing operations earnings per share (diluted) attributable to controlling interests (in dollars per share)	$ 0.46	$ 0.84	$ 1.08	$ 1.68
Weighted average common stock outstanding (in shares)	80,001,360	89,970,871	81,832,607	92,996,289
Weighted average diluted common stock outstanding (in shares)	80,851,538	89,972,300	82,126,530	93,076,064
Consolidated Entity Excluding Consolidated Funds
Revenue:
Other revenue	$ 1,600,000	$ 1,400,000	$ 5,200,000	$ 4,300,000
Operating expenses:
Compensation and benefits	109,700,000	108,000,000.0	284,000,000.0	332,800,000
General and administrative expense	25,400,000	31,700,000	77,600,000	95,300,000
Impairment of goodwill			16,400,000	0
Amortization of acquired intangibles	1,600,000	1,600,000	5,100,000	4,900,000
Depreciation and other amortization	5,200,000	4,400,000	15,600,000	12,200,000
Non-operating income and (expense):
Investment income (loss)	3,900,000	2,300,000	(3,200,000)	11,400,000
Interest income	0	400,000	500,000	1,800,000
Interest expense	(6,900,000)	(8,300,000)	(22,100,000)	(24,100,000)
Gain on sale of Affiliate	7,200,000	0	7,200,000	0
Consolidated Funds
Revenue:
Total revenue	1,400,000	1,900,000	4,600,000	4,900,000
Operating expenses:
Total operating expenses	0	200,000	200,000	400,000
Non-operating income and (expense):
Net consolidated Funds’ investment gains	2,100,000	4,700,000	20,500,000	13,800,000
Net income (loss) attributable to non-controlling interests in consolidated Funds	(3,200,000)	7,600,000	21,300,000	9,600,000
Management fees
Revenue:
Revenue	178,200,000	196,400,000	527,400,000	609,800,000
Management fees | Consolidated Entity Excluding Consolidated Funds
Revenue:
Revenue	178,200,000	196,400,000	527,400,000	609,800,000
Performance fees | Consolidated Entity Excluding Consolidated Funds
Revenue:
Revenue	$ 1,200,000	$ (1,900,000)	$ 2,500,000	$ (6,900,000)