XML 19 R71.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Other Assets (Impact of Derivative Hedging Instruments on AOCI) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Other Assets [Abstract] |  |  |
Balance at beginning of period | $ 3,121 | $ (11,424) | $ (46,721)
Net (loss)/gain on Swaps | (23,342) | 14,545 | 35,297
Amortization of de-designated hedging instruments, net | (2,454) | 0 | 0
Balance at end of period | $ (22,675) | $ 3,121 | $ (11,424)

X
- Definition Other Comprehensive Income (Loss), Amortization of De-Designated Hedging Instruments, after Reclassification and Tax + References No definition available. + Details
Name: | mfa_OtherComprehensiveIncomeLossAmortizationofDeDesignatedHedgingInstrumentsafterReclassificationandTax
Namespace Prefix: | mfa_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e637-108580 + Details
Name: | us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_OtherAssetsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period. + 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 (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 + Details
Name: | us-gaap_UnrealizedGainLossOnDerivatives
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration