Investments in Unconsolidated Entities (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated entities, at fair value	[1]	$ 142,019		$ 142,019		$ 141,620
Earnings (losses) from investments in unconsolidated entities		2,549	$ 11,443	27,786	$ 10,590
LendSure Mortgage Corp [Member]
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated entities, at fair value		27,100		27,100		15,500
Longbridge Financial LLC [Member]
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated entities, at fair value		65,700		65,700		60,600
Mortgage loan originator
Schedule of Equity Method Investments [Line Items]
Earnings (losses) from investments in unconsolidated entities		(6,200)	$ 8,900	5,100	$ 13,200
Investment in Loan Originator
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated entities, at fair value		103,400		103,400		79,500
Variable Interest Entity, Not Primary Beneficiary
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated entities, at fair value		$ 26,800		$ 26,800		$ 13,600

[1] Ellington Financial Inc.'s Condensed Consolidated Balance Sheet includes assets and liabilities of variable interest entities it has consolidated. See Note 9 for additional details on Ellington Financial Inc.'s consolidated variable interest entities.