Investment in Loans (Narrative) (Details) $ in Thousands		3 Months Ended	9 Months Ended
		Sep. 30, 2019 USD ($) loan	Sep. 30, 2019 USD ($) loan	Dec. 31, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans in Process of Foreclosure, Amount				$ 9,100
Unpaid Principal Balance		$ 1,230,004	$ 1,230,004
Loans, at fair value	[1]	1,225,843	1,225,843
Residential mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impairment Losses, Recognized in Earnings		300	700
Unpaid Principal Balance, Impaired Loans		4,100	4,100
Fair Value, Impaired Loans		3,300	3,300
Mortgage Loans in Process of Foreclosure, Amount		9,700	9,700
Unpaid Principal Balance		780,920	780,920
Loans, at fair value		797,728	797,728
Residential mortgage loans | Non-performing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		17,942	17,942
Loans, at fair value		15,940	15,940
Commercial mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		285,252	285,252
Loans, at fair value		$ 260,626	$ 260,626
Commercial mortgage loans | Non-performing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans | loan		5	5
Unpaid Principal Balance		$ 62,300	$ 62,300
Loans, at fair value		38,400	38,400
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impairment Losses, Recognized in Earnings		1,100	4,600
Unpaid Principal Balance, Impaired Loans		58,500	58,500
Fair Value, Impaired Loans		60,600	60,600
Unpaid Principal Balance		148,042	148,042
Loans, at fair value		151,699	151,699
Corporate loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		15,790	15,790
Loans, at fair value		$ 15,790	$ 15,790

[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.