Cash Surrender Value of Life Insurance Policies, net (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Information about cash surrender value of life insurance policies
Cash surrender value of all life insurance policies, net of loans and related accrued interest	$ 41.9	$ 42.0
Borrowed portion
Information about cash surrender value of life insurance policies
Borrowings against cash surrender value of certain policies	35.0	78.4
Premiums and accrued interest on loans against policies	44.0
Amount of borrowed funds used to pay premiums and accrued interest owed		36.0
EMJ \| Borrowed portion
Information about cash surrender value of life insurance policies
Interest on borrowings against cash surrender value of certain life insurance policies (as a percent)	11.76%
Rate at which the portion of the policy cash surrender value earns interest and dividend income (as a percent)	11.26%
Loans and accrued interest outstanding on EMJ's life insurance policies	$ 381.5	$ 351.8
EMJ \| Unborrowed portion
Information about cash surrender value of life insurance policies
Rate at which the portion of the policy cash surrender value earns interest and dividend income (as a percent)	4.00%

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Represents the gross amount of loans borrowed by the entity against cash surrender value of certain life insurance policies.

+ References

No definition available.

+ Details

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- Definition

Represents the fixed interest rate on borrowings against the cash surrender value of certain life insurance policies.

+ References

No definition available.

+ Details

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- Definition

Represents the gross amount of loans borrowed by the entity against cash surrender value of certain life insurance policies to pay premiums and accrued interest owed.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of loans and accrued interest outstanding on life insurance policies.

+ References

No definition available.

+ Details

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- Definition

Represents the premiums and accrued interest on loans outstanding against life insurance policies.

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 4

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6361293&loc=d3e6812-107765

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

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

-Publisher FASB

-Name FASB Technical Bulletin (FTB)

-Number 85-4

-Paragraph 2

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

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

+ Details

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- Definition

Guaranteed minimum interest crediting rate applied to cash values for life insurance contracts which are purchased by corporate entities for purposes such as funding the cost of providing employee benefits and protecting against the loss of "key persons." where investment income is accumulated tax free through the internal build-up of the cash surrender value.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 7

-Section 03

-Paragraph 13

-Subparagraph b

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 60

-Paragraph 60

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.13(b))

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

+ Details

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