Name:	imh_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisChangeInFairValueGainLossIncludedInEarnings
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This element represents change in fair value of trust assets excluding real estate owned due to decreases in the fair value of investment securities-for-sale and of securitized mortgage collateral during the reporting period.

No definition available.

Name:	imh_IncreaseDecreaseInFairValueOfNetTrustAssetsExcludingRealEstateOwned
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Represents the cash inflow from securitization trusts.

No definition available.

Name:	imh_ProceedsFromSecuritizationTrusts
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Represents the amount of bond losses on financial assets transferred in a securitization, asset-backed financing arrangement, or similar transfer that has been accounted for as sales and in which the transferor continues to have involvement.

No definition available.

Name:	imh_QualitativeAndQuantitativeInformationAssetsOrLiabilitiesForTransferorsContinuingInvolvementInSecuritizationOrAssetBackedFinancingArrangementBondLosses
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No definition required.

No definition available.

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- References

No definition available.

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Represents the difference between the unpaid principal balance and fair value of securitized borrowings.

No definition available.

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This element represents change in fair value of trust assets excluding real estate owned due to increases or decreases in the fair value of investment securities-for-sale, securitized mortgage collateral and securitized mortgage borrowings during the reporting period.

No definition available.

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

No definition available.

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Principal amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

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-Name Accounting Standards Codification
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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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This is the principal amount of loans (across all types of loans) that are overdue in payment by a set number of days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Nominal or face amount used to calculate payments on the derivative liability.

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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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.

No definition available.

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This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of long-term debt instruments that have contractual principal amounts and for which the fair value option has been elected.

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This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

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For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

No definition available.

Name:	us-gaap_LiabilitiesFairValueAdjustment
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Balance Type:	credit
Period Type:	duration

- References

No definition available.

Name:	us-gaap_LongTermDebtAbstract
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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

No definition available.

Name:	us-gaap_LongTermDebtFairValue
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- References

No definition available.

Name:	us-gaap_NotionalAmountOfDerivativesAbstract
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The fair value, as of the date of each statement of financial position presented, of loans which are owned but transferred to serve as collateral for the payment of the related debt obligation primarily arising from secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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Name:	us-gaap_PledgedAssetsSeparatelyReportedLoansPledgedAsCollateralAtFairValue
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Data Type:	xbrli:monetaryItemType
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This is the principal amount outstanding for securitized loans only (across all types of loans).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
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Name:	us-gaap_PrincipalAmountOutstandingOnLoansSecuritized
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Fair value of a liability representing servicing arrangements under which the estimated future revenue from contractually specified servicing fees, late charges, and other ancillary revenues are not expected to adequately compensate the servicer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name:	us-gaap_ServicingLiabilityAtFairValueAmount
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

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