XML 110 R99.htm IDEA: XBRL DOCUMENT
v3.20.2

Use of Special Purpose Entities and Variable Interest Entities (Loan Securitization Transaction) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Asset-backed Securities, Securitized Loans and Receivables |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Aggregate fair value | $ 1,681,500 | $ 1,681,500 |  | $ 1,290,029
Outstanding amount of Senior Bonds, at carrying value | 448,893 | 448,893 |  | 570,952
Outstanding amount of Senior Bonds, at fair value | 388,790 | 388,790 |  | 0
Outstanding amount of Senior Bonds, total | 837,683 | 837,683 |  | 570,952
Outstanding amount of Senior Bonds | $ 837,700 | $ 837,700 |  | $ 571,000
Weighted average interest rate | 2.93% | 2.93% |  | 3.68%
Weighted average contractual maturity of Senior Bonds |  | 36 years | 30 years |
Cash received |  | $ 1,193,969 | $ 802,815 |
Debt issuance cost | $ 2,200 | 2,200 |  | $ 2,900
Senior notes |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Cash received | 372,800 | 399,800 |  |
Senior notes | Asset-backed Securities, Securitized Loans and Receivables |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Principal amount of Securitized debt | 1,202,616 | 1,202,616 |  | 802,817
Proceeds from Senior bond sold with Step up feature |  | $ 743,900 | $ 493,200 |
Debt instrument, coupon step-up period |  |  | 36 months |
Senior notes | Asset-backed Securities, Securitized Loans and Receivables | Minimum [Member] |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Debt instrument, basis spread on variable rate |  | 1.00% |  |
Senior notes | Asset-backed Securities, Securitized Loans and Receivables | Maximum [Member] |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Debt instrument, basis spread on variable rate |  | 3.00% |  |
Senior Support Certificates | Asset-backed Securities, Securitized Loans and Receivables |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Principal amount of Securitized debt | $ 266,355 | $ 266,355 |  | $ 275,174

X
- Definition Debt Instrument, Coupon Step-Up Period + References No definition available. + Details
Name: | mfa_DebtInstrumentCouponStepUpPeriod
Namespace Prefix: | mfa_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Financing Receivable, Weighted Average Term to Maturity + References No definition available. + Details
Name: | mfa_FinancingReceivableWeightedAverageTermtoMaturity
Namespace Prefix: | mfa_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Proceeds From Senior Bonds Sold with Step Up Feature + References No definition available. + Details
Name: | mfa_ProceedsFromSeniorBondsSoldwithStepUpFeature
Namespace Prefix: | mfa_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Residential Whole Loans, Aggregate Fair Value + References No definition available. + Details
Name: | mfa_ResidentialWholeLoansAggregateFairValue
Namespace Prefix: | mfa_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Senior Bonds Outstanding, Carrying Value + References No definition available. + Details
Name: | mfa_SeniorBondsOutstandingCarryingValue
Namespace Prefix: | mfa_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Senior Bonds Outstanding, Fair Value + References No definition available. + Details
Name: | mfa_SeniorBondsOutstandingFairValue
Namespace Prefix: | mfa_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Weighted average interest rate of debt outstanding. + References No definition available. + Details
Name: | us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount, before accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28555-108399 + Details
Name: | us-gaap_DeferredFinanceCostsNoncurrentGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Secured financing other than securities sold under agreements to repurchase and securities loaned. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 15 -Paragraph 83 -URI http://asc.fasb.org/extlink&oid=121636179&loc=d3e34841-113949 + Details
Name: | us-gaap_OtherSecuredFinancings
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOfDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

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

X
- Details
Name: | us-gaap_DebtInstrumentAxis=us-gaap_SeniorNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=mfa_RatedandNonRatedCertificatesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |