Commitments, Contingencies and Indemnifications (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Originated Residential Agency loans
Commitments, contingencies and indemnifications
Commitments to originate residential agency loans	$ 273,817	$ 124,020
Unfunded loan commitments
Commitments, contingencies and indemnifications
Loans, net	227,092	161,746
Loans, held for sale at fair value	$ 7,013	$ 4,895