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Goodwill and Acquired Client Relationships - Narrative (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Acquired client relationships [Member]
Goodwill [Line Items]
Impairment	$ 0	$ 102.2
Fair value	864.0	859.4	667.6
Weighted average life	10 years
Future annual amortization expense	100.0
Number of future annual periods of amortization expense presented	5 years
Acquired Client Relationships Mutual Fund Management Contract [Member]
Goodwill [Line Items]
Impairment	0	102.2
Fair value		$ 38.2
Weighted average annual growth rate		10.00%
Discount rate		15.00%

X

- Definition

The annual estimated amortization expense for succeeding fiscal years for intangible assets subject to amortization.

+ References

No definition available.

+ Details

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X

- Definition

Represents the discount rate used as an assumption in calculation of fair value of indefinite-lived intangible assets.

+ References

No definition available.

+ Details

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X

- Definition

Represents the weighted average annual growth rate for assets under management used as an assumption in calculation of fair value of indefinite-lived intangible assets.

+ References

No definition available.

+ Details

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X

- Definition

The number of annual periods annual amortization expense is presented.

+ References

No definition available.

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X

- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Details

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X

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16373-109275

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X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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