Investment in Loans (Schedule of Consumer Mortgage Loans) (Details) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		$ 1,230,004
Unamortized Premium (Discount)		(106,592)
Amortized Cost			$ 2,970,306
Loans, at fair value	[1]	$ 1,225,843
Weighted Average
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted average life		5 years 128 days
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		$ 148,042
Unamortized Premium (Discount)		1,739
Amortized Cost		149,781
Gains		2,357
Losses		(439)
Loans, at fair value		$ 151,699
Consumer loans | Weighted Average
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted average life		270 days
Delinquency (Days)		5 days

[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.