Investment in Loans Investment in Loans (Schedule of Corporate Loans) (Details) - USD ($) $ in Thousands		9 Months Ended	12 Months Ended
		Sep. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		$ 1,414,410	$ 1,387,733
Loans, at fair value	[1]	1,442,612	1,412,426
Corporate loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		7,063	18,415
Loans, at fair value		$ 7,063	$ 18,510
Weighted Average
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Coupon		3.98%	4.23%
Weighted average life		4 years 4 months 17 days	5 years 10 months 24 days
Weighted Average | Corporate loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted Average Coupon		19.43%	17.62%
Weighted average life		1 year 11 months 23 days	10 months 13 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.