Financing Receivable, Loans Sold to Third Party Investors

No definition available.

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Period Type:	instant

- Definition

Guarantor Obligations, Short-Term

+ References

No definition available.

+ Details

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Namespace Prefix:	fmer_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum percentage adverse change in prepayment speed.

+ References

No definition available.

+ Details

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Namespace Prefix:	fmer_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum percentage adverse change in prepayment speed.

+ References

No definition available.

+ Details

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Namespace Prefix:	fmer_
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Period Type:	duration

- Definition

Mortgage Servicing Rights.

+ References

No definition available.

+ Details

Name:	fmer_MortgageServicingRights
Namespace Prefix:	fmer_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of variation in prepayment speed.

+ References

No definition available.

+ Details

Name:	fmer_PercentageOfVariationInPrepaymentSpeed
Namespace Prefix:	fmer_
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- Definition

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122596-111746

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This is the result of the principal amount outstanding of total loans managed or securitized less securitized loans and loans that are in the process of being securitized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

+ Details

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

- Definition

Reflects, by transferred financial asset type, the amount of sales proceeds in excess of or deficient from the sum of the carrying amounts of transferred financial assets plus transaction costs, including those transactions in which the seller/transferor has continuing involvement with the financial assets that have been transferred.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107207-111719

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 10

-Section 40

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=45353237&loc=d3e96813-111708

+ Details

Name:	us-gaap_SecuritizationFinancialAssetForWhichTransferIsAccountedAsSaleGainLossOnSale
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction that continue to be recognized in the statement of financial position. Includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_ServicingAssetsAtFairValueLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ResidentialMortgageMember
Namespace Prefix:
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- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=fmer_ManufacturedHousingMember
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(Narrative) Details) (USD $)	3 Months Ended
(Narrative) Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Servicing Assets at Fair Value [Line Items]
Guarantor Obligations, Short-Term			$ 199,800,000fmer_GuarantorObligationsShortTerm
Mortgage Servicing Rights	21,490,000fmer_MortgageServicingRights	22,469,000fmer_MortgageServicingRights	22,011,000fmer_MortgageServicingRights	22,760,000fmer_MortgageServicingRights
Unpaid principal balances from sale of residential mortgage loans	50,300,000	65,600,000
Recognized pretax gains	600,000	1,300,000
Related mortgage servicing rights from loans sold and receives servicing fees	45,200,000	57,100,000
Minimum percentage adverse change in prepayment speed	10.00%
Maximum percentage adverse change in prepayment speed	25.00%
Percentage of variation in prepayment speed	10.00%
Residential Mortgages
Servicing Assets at Fair Value [Line Items]
Loan servicing fees	1,600,000	1,600,000
Servicing Asset	2,600,000,000	2,700,000,000
Manufactured Housing
Servicing Assets at Fair Value [Line Items]
Financing Receivable, Loans Sold to Third Party Investors	$ 3,700,000	$ 6,400,000