Short-Term Debt - Warehouse Line of Credit (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Short-term Debt
Warehouse line of credit	$ 104,620	$ 133,811
Paid swap margin calls on our derivatives	137,100	104,700
Derivative instruments at fair value	2,205	5,833
Derivative instruments at fair value	93,317	52,197
Warehouse Line Facility
Short-term Debt
Warehouse line of credit	104,800	133,800
Agency MBS
Short-term Debt
Pledged as collateral	1,680,000	3,420,000
Derivative instruments at fair value	2,200
Derivative instruments at fair value	93,300
Non-Agency MBS
Short-term Debt
Pledged as collateral	165,000	535,000
Interest rate swap agreements
Short-term Debt
Derivative instruments at fair value		5,300
TBA Agency MBS
Short-term Debt
Derivative instruments at fair value	$ 2,205	$ 531

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