Investment in Loans (Schedule of 90 Days or More Past Due) (Details) $ in Thousands	Sep. 30, 2019 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	$ 1,230,004
Loans, at fair value	1,225,843	[1]
Commercial mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	285,252
Loans, at fair value	260,626
Residential mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	780,920
Loans, at fair value	797,728
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	148,042
Loans, at fair value	151,699
Non-accrual status [Member] | Commercial mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at fair value	10,700
Non-accrual status [Member] | Commercial mortgage loans | 90 Days or More Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	62,286
Loans, at fair value	38,407
Non-accrual status [Member] | Residential mortgage loans | 90 Days or More Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	18,961
Loans, at fair value	16,521
Non-accrual status [Member] | Consumer loans | 90 Days or More Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance	1,367
Loans, at fair value	$ 1,254

[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.