Refers to assets before elimination and reclassification.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For consolidation, the elimination of the parent company's ownership amount in the subsidiaries included in the consolidation.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

For consolidation, the reclassification of the various subsidiaries' asset and liability amounts relating to common transactions.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The cost of borrowed funds from affiliates accounted for as interest that was charged against earnings during the period.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Aggregate premium revenue less insurance benefit costs including losses, settlement expenses, acquisition costs amortized, policyholder dividends, and other underwriting expenses.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ 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 210.5-02.18)

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 7

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 18

-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(c),9(a))

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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 10

-Subparagraph (c)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Definition

Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 16

-Article 12

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

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-Section S99

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-Subparagraph (SX 210.7-04.2)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 2

-Article 7

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- Definition

The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.3)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 3

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- Definition

Reflects the sum of all other revenue and income recognized by the entity in the period not otherwise specified in the income statement.

+ References

+ Details

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- Definition

Amount, after premiums ceded to other entities and premiums assumed by the entity, of property and casualty premiums earned.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

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-Subparagraph (SX 210.7-04.1)

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-Name Regulation S-X (SX)

-Number 210

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-SubTopic 605

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-Name Accounting Standards Codification

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-SubTopic 605

-Section 50

-Paragraph 1

-Subparagraph (b),(c)

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SEGMENT INFORMATION - Summarized financial information by segment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of operating profit loss from segment to consolidated
Premiums earned									$ 540,722	$ 515,506	$ 458,846
Underwriting profit (loss)									(10,124)emci_UnderwritingProfitLoss	10,873emci_UnderwritingProfitLoss	1,634emci_UnderwritingProfitLoss
Net investment income (loss)									46,465us-gaap_NetInvestmentIncome	43,022us-gaap_NetInvestmentIncome	44,145us-gaap_NetInvestmentIncome
Realized investment gains									4,349us-gaap_GainLossOnInvestments	8,997us-gaap_GainLossOnInvestments	8,017us-gaap_GainLossOnInvestments
Other income (loss)									2,931us-gaap_OtherIncome	460us-gaap_OtherIncome	834us-gaap_OtherIncome
Interest expense									337emci_InterestExpenseToAffiliates	384emci_InterestExpenseToAffiliates	900emci_InterestExpenseToAffiliates
Other expenses									2,377us-gaap_OtherCostAndExpenseOperating	2,115us-gaap_OtherCostAndExpenseOperating	2,097us-gaap_OtherCostAndExpenseOperating
Income before income tax expense	23,865	1,883	270	14,889	22,831	9,564	7,949	20,509	40,907	60,853	51,633
Reconciliation of assets from segment to consolidated
Assets	1,994,576				1,816,966				1,994,576	1,816,966
Eliminations	(495,288)emci_AssetsEliminations				(441,984)emci_AssetsEliminations				(495,288)emci_AssetsEliminations	(441,984)emci_AssetsEliminations
Reclassifications	(1,468)emci_AssetsReclassifications				(481)emci_AssetsReclassifications				(1,468)emci_AssetsReclassifications	(481)emci_AssetsReclassifications
Total assets	1,497,820us-gaap_Assets				1,374,501us-gaap_Assets				1,497,820us-gaap_Assets	1,374,501us-gaap_Assets
Property and casualty insurance [Member]
Reconciliation of operating profit loss from segment to consolidated
Premiums earned									422,381	392,719	357,139
Underwriting profit (loss)									(12,309)	(10,435)	(8,207)
Net investment income (loss)									33,509	31,397	32,214
Realized investment gains									2,938	7,525	7,348
Other income (loss)									695	765	774
Interest expense									337	384	900
Other expenses									793	751	798
Income before income tax expense									23,703	28,117	30,431
Reconciliation of assets from segment to consolidated
Assets	1,057,429				974,743				1,057,429	974,743
Eliminations	0				0				0	0
Reclassifications	(909)				0				(909)	0
Total assets	1,056,520				974,743				1,056,520	974,743
Reinsurance [Member]
Reconciliation of operating profit loss from segment to consolidated
Premiums earned									118,341	122,787	101,707
Underwriting profit (loss)									2,185	21,308	9,841
Net investment income (loss)									12,968	11,635	11,941
Realized investment gains									1,411	1,472	669
Other income (loss)									2,236	(305)	60
Interest expense									0	0	0
Other expenses									0	0	0
Income before income tax expense									18,800	34,110	22,511
Reconciliation of assets from segment to consolidated
Assets	434,139				386,855				434,139	386,855
Eliminations	0				0				0	0
Reclassifications	0				0				0	0
Total assets	434,139				386,855				434,139	386,855
Parent company [Member]
Reconciliation of operating profit loss from segment to consolidated
Premiums earned									0	0	0
Underwriting profit (loss)									0	0	0
Net investment income (loss)									(12)	(10)	(10)
Realized investment gains									0	0	0
Other income (loss)									0	0	0
Interest expense									0	0	0
Other expenses									1,584	1,364	1,299
Income before income tax expense									(1,596)	(1,374)	(1,309)
Reconciliation of assets from segment to consolidated
Assets	503,008				455,368				503,008	455,368
Eliminations	(495,288)				(441,984)				(495,288)	(441,984)
Reclassifications	(559)				(481)				(559)	(481)
Total assets	$ 7,161				$ 12,903				$ 7,161	$ 12,903