The reserve for guarantee losses is a liability account in the consolidated balance sheets that reflects an estimate of incurred credit losses related to the guaranty of unconsolidated trusts and other credit guarantees

No definition available.

+ Details

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Namespace Prefix:	agm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of writeoff of financing receivable, charged against allowance for credit loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 79
-URI http://asc.fasb.org/extlink&oid=121647567&loc=SL82922352-210448

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

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

- Definition

Amount of expense related to credit loss from transactions other than loan and lease transactions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(11))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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- Details

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- Details

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Guarantees - Reserve For Losses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Guarantor Obligations [Line Items]
Reserve for losses	$ 3,020		$ 3,020				$ 2,164
Release of losses	(400)	$ (158)	(7)	$ (287)
Farm & Ranch
Guarantor Obligations [Line Items]
Reserve for losses	1,650	1,880	1,650	1,880	$ 2,020	$ 2,016	2,164	$ 2,038	$ 2,167	$ 2,167
Release of losses	(370)	(158)	(366)	(287)
Charge-offs	394		394
Rural Utilities
Guarantor Obligations [Line Items]
Reserve for losses	1,370	0	1,370	0	$ 1,400	$ 1,011	0	$ 0	$ 0	$ 0
Release of losses	(30)	$ 0	359	$ 0
Charge-offs	0		0
LTSPCs and Farmer Mac Guaranteed Securities \| Farm & Ranch
Guarantor Obligations [Line Items]
Reserve for losses	1,650		1,650				2,164
Charge-offs	0		0
LTSPCs \| Rural Utilities
Guarantor Obligations [Line Items]
Reserve for losses	$ 1,370		$ 1,370				$ 0