ASBESTOS AND ENVIRONMENTAL CLAIMS (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended	72 Months Ended
Dec. 31, 2014 policyholder claim lawsuit	Dec. 31, 2014 claim lawsuit	Dec. 31, 2013
Liability for Asbestos and Environmental Claims [Abstract]
Average asbestos and environmental losses paid by company per year over past five years	$ 1,720
Reserves for asbestos and environmental related claims, before reinsurance	9,420	9,420	9,643
Reserves for asbestos and environmental related claims, net of reinsurance	9,296	9,296	8,950
Number of asbestos bodily injury lawsuits	1,849	1,849
Number of policyholders producing recent higher paid asbestos amounts	1
Company's share of asbestos related claims settled		$ 7,294emci_LargeAsbestosClaimsPaid
Number of asbestos exposure claims associated with furnace manufacturer, a former policyholder, remain open	690	690

Average asbestos and environmental losses paid per year over most recent five years.

No definition available.

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- Definition

Refers to the Company's share of selected material asbestos claim settlements.

+ References

No definition available.

+ Details

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- Definition

Refers to number of asbestos bodily injury lawsuits.

+ References

No definition available.

+ Details

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- Definition

Refers to number of asbestos exposure claims associated with former policyholder remain open.

+ References

No definition available.

+ Details

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- Definition

Refers to the number of policyholders producing the recent rise in asbestos claim payments.

+ References

No definition available.

+ Details

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- Details

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- Definition

Carrying amount as of the balance sheet date of reserves for the costs of settling insured claims and costs incurred in the claims settlement process attributable to asbestos and environmental claims, before estimated recoveries from reinsurers.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 40

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437

+ Details

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- Definition

+ References

+ Details

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