XML 63 R53.htm IDEA: XBRL DOCUMENT v3.23.1

Securities, at Fair Value - Residential Mortgage Securities (Details) - USD ($) $ in Thousands		Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Fair Value	[1]	$ 504,639	$ 333,364
Agency MBS
Debt Securities, Available-for-sale [Line Items]
Principal/ Current Face		299,508	131,165
Purchase Premiums		1,175	860
Accretable Purchase Discounts		(65)	0
Discount Designated as Credit Reserve		0	0
Gross Amortized Cost		300,618	132,025
Gross Unrealized Gains		1,470	0
Gross Unrealized Losses		(248)	(325)
Net Unrealized Gain/(Loss)		1,222	(325)
Fair Value		301,840	131,700
Other Securities
Debt Securities, Available-for-sale [Line Items]
Principal/ Current Face		215,103	215,649
Purchase Premiums		19,576	18,344
Accretable Purchase Discounts		(6,092)	(6,272)
Discount Designated as Credit Reserve		(46,332)	(46,332)
Gross Amortized Cost		182,255	181,389
Gross Unrealized Gains		20,859	21,473
Gross Unrealized Losses		(315)	(1,198)
Net Unrealized Gain/(Loss)		20,544	20,275
Fair Value		202,799	201,664
Total residential mortgage securities
Debt Securities, Available-for-sale [Line Items]
Principal/ Current Face		514,611	346,814
Purchase Premiums		20,751	19,204
Accretable Purchase Discounts		(6,157)	(6,272)
Discount Designated as Credit Reserve		(46,332)	(46,332)
Gross Amortized Cost		482,873	313,414
Gross Unrealized Gains			21,473	$ 22,329
Gross Unrealized Losses		(563)	(1,523)
Net Unrealized Gain/(Loss)		21,766	19,950
Fair Value		504,639	333,364
CRT, Fair Value Option
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains		195	131
Gross Unrealized Losses		(315)	(1,200)
Fair Value		49,400	48,600
Non-Agency MBS
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains		437
Gross Unrealized Losses			0
Fair Value		$ 24,800	$ 24,600
[1] See Note 6 for information regarding the Company’s pledged assets.

X

- Definition

Represents the amount of unamortized accretable purchase discounts related to available-for-sale securities.

+ References

No definition available.

+ Details

Name:	mfa_AvailableForSaleSecuritiesAccretablePurchaseDiscounts
Namespace Prefix:	mfa_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Represent the amount of purchase discount designated as credit reserves and not expected to be accreted into interest income. Also includes other than temporary impairments which are not expected to be accreted into interest income.

+ References

No definition available.

+ Details

Name:	mfa_AvailableForSaleSecuritiesDiscountDesignatedAsCreditReserveAndOtherThanTemporaryImpairments
Namespace Prefix:	mfa_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Represents the amount of unamortized purchase premiums related to available-for-sale securities.

+ References

No definition available.

+ Details

Name:	mfa_AvailableForSaleSecuritiesPurchasePremiums
Namespace Prefix:	mfa_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

+ Details

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

X

- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

+ Details

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

X

- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

+ Details

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

X

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

+ Details

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

X

- Definition

Amount, before tax, of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

No definition available.

+ Details

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

X

- Definition

For investments which are quantified by principal amount, the principle balance held at close of period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=99383244&loc=d3e12121-115841

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-12B(Column B))
-URI https://asc.fasb.org/extlink&oid=122147990&loc=d3e611197-123010

+ Details

Name:	us-gaap_InvestmentOwnedBalancePrincipalAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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_FinancialInstrumentAxis=mfa_AgencyMBSMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=mfa_OtherSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=mfa_ResidentialMortgageSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=mfa_CRTFairValueOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=mfa_NonAgencyMBSMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: