Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

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- Definition

Other investments not otherwise specified in the taxonomy.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 12

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph g

-Article 7

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(f,g))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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- Details

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (bb)

-URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5710-111685

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- Definition

The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

+ References

+ Details

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 5A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=28200181&loc=SL6759159-111685

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- Definition

Number of investments held.

+ References

No definition available.

+ Details

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- Definition

The largest investment which the entity has made in a single fund.

+ References

No definition available.

+ Details

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Investment Securities (Hedge Funds and Private Equity Funds) (Details) (USD $) In Millions, unless otherwise specified						9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 Hedge funds fund	Sep. 30, 2014 Private equity funds fund	Sep. 30, 2014 Hedge and private equity funds included in other long-term investments	Sep. 30, 2014 Prospector Offshore Fund Ltd [Member]	Sep. 30, 2014 Prospector Turtle Fund [Member]	Sep. 30, 2014 Prospector Funds [Member]	Dec. 31, 2013 Prospector Funds [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage						67.00%	69.00%
Other Investments	$ 320.9	$ 288.9						$ 95.4	$ 112.4
Largest single fund investment					19.5
Number of investments			14	32
Variable Interest Entity, Consolidated, Carrying Amount, Assets								223.5	249.2
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities								82.7	90.6
Total non-controlling interests	$ 488.7	$ 491.9						$ 45.4	$ 46.2