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Investment Securities (Restrictions on Redemption Frequency and Advance Notice Requirements) (Details) (Hedge funds, USD $) In Millions, unless otherwise specified	Mar. 31, 2014
Investment securities
Other long-term investments	$ 126.2
Distributions from inactive hedge funds	2.1
Redemption requests	2.2
30-59 days notice
Investment securities
Other long-term investments	34.3
Fair Value Investments Entities that Calculate Net Asset Value Per Share Investment Redemption Notice Period60 To89 Days [Member]
Investment securities
Other long-term investments	56.2
Fair Value Investments Entities that Calculate Net Asset Value Per Share Investment Redemption Notice Period90 To119 Days [Member]
Investment securities
Other long-term investments	21.2
120+ days notice
Investment securities
Other long-term investments	14.5
Monthly
Investment securities
Other long-term investments	10.4
Monthly | 30-59 days notice
Investment securities
Other long-term investments	4.9
Monthly | Fair Value Investments Entities that Calculate Net Asset Value Per Share Investment Redemption Notice Period60 To89 Days [Member]
Investment securities
Other long-term investments	0
Monthly | Fair Value Investments Entities that Calculate Net Asset Value Per Share Investment Redemption Notice Period90 To119 Days [Member]
Investment securities
Other long-term investments	0
Monthly | 120+ days notice
Investment securities
Other long-term investments	5.5
Quarterly
Investment securities
Other long-term investments	80.5
Quarterly | 30-59 days notice
Investment securities
Other long-term investments	29.4
Quarterly | Fair Value Investments Entities that Calculate Net Asset Value Per Share Investment Redemption Notice Period60 To89 Days [Member]
Investment securities
Other long-term investments	30.4
Quarterly | Fair Value Investments Entities that Calculate Net Asset Value Per Share Investment Redemption Notice Period90 To119 Days [Member]
Investment securities
Other long-term investments	11.9
Quarterly | 120+ days notice
Investment securities
Other long-term investments	8.8
Semi-annual
Investment securities
Other long-term investments	25.8
Semi-annual | 30-59 days notice
Investment securities
Other long-term investments	0
Semi-annual | Fair Value Investments Entities that Calculate Net Asset Value Per Share Investment Redemption Notice Period60 To89 Days [Member]
Investment securities
Other long-term investments	25.8
Semi-annual | Fair Value Investments Entities that Calculate Net Asset Value Per Share Investment Redemption Notice Period90 To119 Days [Member]
Investment securities
Other long-term investments	0
Semi-annual | 120+ days notice
Investment securities
Other long-term investments	0
Annual
Investment securities
Other long-term investments	9.5
Annual | 30-59 days notice
Investment securities
Other long-term investments	0
Annual | Fair Value Investments Entities that Calculate Net Asset Value Per Share Investment Redemption Notice Period60 To89 Days [Member]
Investment securities
Other long-term investments	0
Annual | Fair Value Investments Entities that Calculate Net Asset Value Per Share Investment Redemption Notice Period90 To119 Days [Member]
Investment securities
Other long-term investments	9.3
Annual | 120+ days notice
Investment securities
Other long-term investments	$ 0.2

X

- Details

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X

- Definition

Amount of other investments classified as trading.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.4)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Trading Securities

-URI http://asc.fasb.org/extlink&oid=6526789



Reference 5: 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.(a),1(c),(d),(e),(f),(g))

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



Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph c, d, e, f, g

-Article 7

+ Details

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X

- Definition

Distributions pending from hedge funds that are no longer active and are in process of disposing their underlying investments.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

The amount of redemption requests submitted for investments for hedge funds.

+ References

No definition available.

+ Details

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