This element represents number of mortgage loans on real estate with outstanding principal balance.

No definition available.

Name:	ifcn_MortgageLoansOnRealEstateNumberOfLoansOutstandingPrincipalBalance
Namespace Prefix:	ifcn_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Weighted average interest rate on mortgage loans.

+ References

No definition available.

+ Details

Name:	ifcn_MortgageLoansWeightedAverageInterestRate
Namespace Prefix:	ifcn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Mortgage Loans on Real Estate, New Mortgage Loans, Discount

+ References

No definition available.

+ Details

Name:	ifcn_MortgageLoansonRealEstateNewMortgageLoansDiscount
Namespace Prefix:	ifcn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Mortgage Loans on Real Estate, New Mortgage Loans, Expenses

+ References

No definition available.

+ Details

Name:	ifcn_MortgageLoansonRealEstateNewMortgageLoansExpenses
Namespace Prefix:	ifcn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Mortgage Loans on Real Estate, New Mortgage Loans, Number of Extensions Available

+ References

No definition available.

+ Details

Name:	ifcn_MortgageLoansonRealEstateNewMortgageLoansNumberofExtensionsAvailable
Namespace Prefix:	ifcn_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Mortgage Loans on Real Estate, Number of Loans Acquired

+ References

No definition available.

+ Details

Name:	ifcn_MortgageLoansonRealEstateNumberofLoansAcquired
Namespace Prefix:	ifcn_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82921503&loc=d3e21338-158488

+ Details

Name:	us-gaap_AllowanceForLoanAndLeaseLossesRealEstate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Interest and fee income from mortgage loans considered to be held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.1)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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

- Definition

The carrying amount of the outstanding balance due under the mortgage loan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule IV)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29)
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

+ Details

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

- Definition

The stated interest rate on the mortgage loan receivable or the weighted average interest rate on a group of loans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29)
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule IV)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

+ Details

Name:	us-gaap_MortgageLoansOnRealEstateInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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

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

- Definition

Indicates the number of mortgages under each classification.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29.3)
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule IV)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

+ Details

Name:	us-gaap_MortgageLoansOnRealEstateNumberOfLoans
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=us-gaap_NonperformingFinancingReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=us-gaap_MortgageReceivablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=us-gaap_PerformingFinancingReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

MORTGAGE LOANS, NET (Details Textual)	3 Months Ended		12 Months Ended
MORTGAGE LOANS, NET (Details Textual)	Mar. 31, 2018 USD ($) Loan	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($) Loan	Dec. 31, 2016 Loan
Mortgage Loans on Real Estate [Line Items]
Mortgage loan income	$ 625,000	$ 8,000
Nonperforming Financing Receivable [Member]
Mortgage Loans on Real Estate [Line Items]
Number of loans (in loans) \| Loan				2
Aggregate average principal and interest balance	$ 0
Mortgage Loans On Real Estate Number Of Loans, Outstanding Principal Balance \| Loan	2
Mortgage Receivable [Member]
Mortgage Loans on Real Estate [Line Items]
Number of loans (in loans) \| Loan	5			4
Aggregate average principal and interest balance	$ 19,700,000		$ 19,700,000
Valuation allowance	$ (12,700,000)		$ (12,700,000)
Number of loans acquired \| Loan	1
Discount on loans acquired	$ 13,100,000
Expenses of acquired loans	$ 100,000
Number of extensions available for loans acquired	1
Annual interest rate of loans acquired	8.50%
Mortgage Receivable [Member] \| Performing Financing Receivable [Member]
Mortgage Loans on Real Estate [Line Items]
Number of loans (in loans) \| Loan	3		2
Interest rate	10.00%		9.70%
Mortgage Receivable [Member] \| Nonperforming Financing Receivable [Member]
Mortgage Loans on Real Estate [Line Items]
Aggregate average principal and interest balance	$ 0