v3.25.4

Financing Agreements - Convertible Senior Notes (Details)		1 Months Ended		3 Months Ended	12 Months Ended
	Apr. 17, 2024 USD ($)	Jan. 31, 2024 USD ($)	Jun. 30, 2019 USD ($) $ / shares	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2025	Dec. 31, 2024	Feb. 28, 2023 USD ($)
Convertible Senior Notes \| 6.25% Convertible Senior Notes
Debt Instrument [Line Items]
Proceeds from issuance of convertible senior notes			$ 230,000,000.0
Proceed from debt net of offering expenses and underwriting discount			$ 223,300,000
Stated interest rate (as a percent)			6.25%			6.25%
Conversion ratio			31.4346
Face amount			$ 1,000
Conversion price (in dollars per share) \| $ / shares			$ 31.81
Effective interest rate			6.94%
Authorized repurchase amount								$ 100,000,000
Principal amount of debt repurchased				$ 39,900,000	$ 20,400,000
Debt instrument, repurchase amount				39,800,000	20,200,000
Gain (loss) on repurchase of debt instrument				$ (100,000)	$ 100,000
Senior Notes \| 8.875% Senior Notes due 2029
Debt Instrument [Line Items]
Proceed from debt net of offering expenses and underwriting discount		$ 110,600,000
Stated interest rate (as a percent)		8.875%				8.875%	8.875%
Face amount		$ 115,000,000.0
Effective interest rate		9.83%
Redemption price as percentage of principal amount		100.00%
Senior Notes \| 9.00% Senior Notes due 2029
Debt Instrument [Line Items]
Proceed from debt net of offering expenses and underwriting discount	$ 72,000,000.0
Stated interest rate (as a percent)	9.00%					9.00%	9.00%
Face amount	$ 75,000,000.0
Effective interest rate	9.94%
Redemption price as percentage of principal amount	100.00%

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MFA FINANCIAL, INC. 10-K