Investment in Loans Investment in Loans (Schedule of Residential Mortgage Loans: Performance) (Details) $ in Thousands	Jun. 30, 2019 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	$ 1,100,062
Loans, at fair value	1,091,523	[1]
Residential mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	652,119
Loans, at fair value	663,880
Residential mortgage loans | Performing Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	15,923
Loans, at fair value	13,866
Residential mortgage loans | Non-performing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	18,641
Loans, at fair value	$ 16,996

[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.