XML 49 R38.htm IDEA: XBRL DOCUMENT
v3.19.1

Farmer Mac Guaranteed Securities and USDA Securities - Narrative (Details) - Institutional Credit [Member] - Farmer Mac Guaranteed Securities [Member] - position | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale, securities in unrealized loss positions | 28 | 38
Held-to-maturity, securities in unrealized loss positions | 32 | 43
Debt securities, available-for-sale, continuous unrealized loss position 12 months or longer | 24 | 21

X
- Definition Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
Name: | us-gaap_AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer. + References No definition available. + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- 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_ScheduleOfAvailableForSaleSecuritiesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=agm_InstitutionalCreditMemberMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |