Amount used to represent the attrition when calculating the fair value of amortizable asset management contracts

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

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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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No definition available.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Percentage of assumed long-term growth in revenues, used as an input to measure fair value.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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Acquisitions QS Investors Acquisition - Fair Value Assumptions (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2014	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	May. 30, 2014
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Business Combination, Contingent Consideration, Liability		$ 84,585	$ 110,784	$ 29,553
Business Combination, Contingent Consideration, Liability, Current		26,396
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability		(33,375)	0	5,000
Revenues		2,660,844	2,819,106	2,741,757
QS Investors [Domain]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Revenues			12,340
QS Investors [Domain]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Business Combination, Contingent Consideration, Liability		13,749	13,553	$ 0	$ 13,370
Business Combination, Contingent Consideration, Liability, Current		6,549
Fund management contracts [Member] \| QS Investors [Domain]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years
Fair Value, Inputs, Level 3 [Member] \| Fund management contracts [Member] \| QS Investors [Domain]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Attrition Rate	(10.00%)
Fair Value Inputs, Discount Rate	15.00%
Fair Value, Inputs, Level 3 [Member] \| Contingent Consideration Liability \| QS Investors [Domain] \| Contingent payment due on second anniversary of acquisition
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Discount Rate	1.20%
Fair Value, Inputs, Level 3 [Member] \| Contingent Consideration Liability \| QS Investors [Domain] \| Contingent Payment due on fourth anniversary of acquisition
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Discount Rate	2.10%
Minimum [Member] \| Fair Value, Inputs, Level 3 [Member] \| Contingent Consideration Liability \| QS Investors [Domain]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate	0.00%
Maximum [Member] \| Fair Value, Inputs, Level 3 [Member] \| Contingent Consideration Liability \| QS Investors [Domain]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate	10.00%
Weighted Average [Member] \| Fair Value, Inputs, Level 3 [Member] \| Contingent Consideration Liability \| QS Investors [Domain]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate	6.00%
Other changes in Fair Value [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability		2,484	(7,350)
Other changes in Fair Value [Member] \| QS Investors [Domain]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability		$ 196	$ 183