Securitization Transactions (Schedule of Residential Loan Securitizations) (Details) - Non-QM loan securitization - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
November 2017 [Member]
Securitization Transactions [Line Items]
Total Face Amount of Certificates Issued	$ 141,233	$ 141,233
Economic interest retained	5.10%	5.10%
Purchase of certificates	$ 700	$ 700
November 2018 [Member]
Securitization Transactions [Line Items]
Total Face Amount of Certificates Issued	$ 232,518	$ 232,518
Economic interest retained	5.70%	5.70%
Purchase of certificates	$ 1,300	$ 1,300
June 2019 [Member]
Securitization Transactions [Line Items]
Total Face Amount of Certificates Issued	$ 226,913
Economic interest retained	6.10%
Purchase of certificates	$ 1,200
The Company [Member] | November 2017 [Member]
Securitization Transactions [Line Items]
Principal Balance of Loans Transferred to the Depositor	141,233	141,233
The Company [Member] | November 2018 [Member]
Securitization Transactions [Line Items]
Principal Balance of Loans Transferred to the Depositor	232,518	$ 232,518
The Company [Member] | June 2019 [Member]
Securitization Transactions [Line Items]
Principal Balance of Loans Transferred to the Depositor	$ 226,913