Fair Value Assumptions, Average Projected Growth Rate

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Fair Value Assumptions, Discount Rate For Assets Based Fees

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Fair Value Assumptions, Market Participant Tax Rate

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Goodwill and Acquired Client Relationships - Additional Information (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill
Goodwill impairment		$ 0
Intangible future amortization expense in 2022	$ 30,000,000		$ 30,000,000
Intangible future amortization expense in 2023	75,000,000		75,000,000
Acquired Client Relationships
Goodwill
Impairment of indefinite-lived intangibles	$ 35,000,000.0		0
Fair value assumptions, average projected growth rate	(9.00%)
Fair value assumptions, discount rate for asset based fees	14.50%
Fair value assumptions, market participant tax rate	25.00%
Acquired Client Relationships \| Closure Of Certain Retail Investment Products
Goodwill
Impairment of indefinite-lived intangibles	$ 16,100,000
Carrying value of indefinite-lived intangibles	0		0
Acquired Client Relationships \| Controlling interests
Goodwill
Impairment of indefinite-lived intangibles	31,200,000
Acquired Client Relationships
Goodwill
Intangible amortization expense			93,400,000	$ 114,400,000	$ 86,400,000
Intangible future amortization expense in 2020	60,000,000		60,000,000
Intangible future amortization expense in 2021	30,000,000		30,000,000
Intangible future amortization expense in 2023	30,000,000		30,000,000
Intangible future amortization expense in 2024	20,000,000		20,000,000
Impairment of indefinite-lived intangibles			51,100,000	400,000
Carrying value of indefinite-lived intangibles	$ 972,200,000		$ 972,200,000	$ 1,006,300,000	$ 1,028,700,000