Guarantees and Other Off-Balance Sheet Credit Exposures - Other Off-Balance Sheet Credit Exposure (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Guarantor Obligations [Line Items]
Unsettled securities purchased under agreements to resell, net	$ 27,811	$ 10,650
UPB Of Off-Balance Sheet Credit Exposure	45,609	27,314
Commitments with FVO election	0	2,000
Unsettled SSUAR	1,900	400
Multifamily
Guarantor Obligations [Line Items]
Mortgage loan purchase commitments	14,010	12,416
Other commitments	$ 3,788	$ 4,248

Represents commitments for which we have elected the fair value option

No definition available.

Name:	fmcc_CommitmentsWithFVOElection
Namespace Prefix:	fmcc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represent primary Multifamily mortgage loan purchase commitments

+ References

No definition available.

+ Details

Name:	fmcc_MortgageLoanPurchaseCommitments
Namespace Prefix:	fmcc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents unfunded portion of revolving lines of credit, liquidity guarantees, and other commitments

+ References

No definition available.

+ Details

Name:	fmcc_OtherLoanCommitments
Namespace Prefix:	fmcc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents total notional value Of off-Balance Sheet value credit exposure

+ References

No definition available.

+ Details

Name:	fmcc_UnpaidPrincipalBalanceOfoffBalanceSheetCreditExposure
Namespace Prefix:	fmcc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represent unsettled securities sold under agreements to repurchase

+ References

No definition available.

+ Details

Name:	fmcc_UnsettledSSUAR
Namespace Prefix:	fmcc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Unsettled securities purchased under agreements to resell, net

+ References

No definition available.

+ Details

Name:	fmcc_UnsettledSecuritiesPurchasedUnderAgreementsToResellNet
Namespace Prefix:	fmcc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

+ Details

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

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=srt_MultifamilyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: