Financing Receivable, Loans Sold to Third Party Investors

No definition available.

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- Definition

Guarantor Obligations, Short-Term

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Maximum percentage adverse change in prepayment speed.

+ References

No definition available.

+ Details

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- Definition

Minimum percentage adverse change in prepayment speed.

+ References

No definition available.

+ Details

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- Definition

Mortgage Servicing Rights.

+ References

No definition available.

+ Details

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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

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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=56950315&loc=d3e122596-111746

+ Details

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Balance Type:	credit
Period Type:	duration

- 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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Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=fmer_ManufacturedHousingMember
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Period Type:

(Narrative) Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
(Narrative) Details) - USD ($) $ in Thousands	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Servicing Assets at Fair Value [Line Items]
Guarantor Obligations, Short-Term	$ 132,700		$ 132,700
Mortgage Servicing Rights	$ 19,767	$ 22,189	$ 19,767	$ 22,189	$ 20,635	$ 22,011	$ 22,150	$ 22,760
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%		10.00%
Residential Mortgages
Servicing Assets at Fair Value [Line Items]
Loan servicing fees	$ 1,500	1,600	$ 4,800	4,900
Servicing Asset	2,400,000	$ 2,600,000	2,400,000	$ 2,600,000
Manufactured Housing
Servicing Assets at Fair Value [Line Items]
Financing Receivable, Loans Sold to Third Party Investors	$ 3,700		$ 3,700