Derivatives - Offsetting Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Offsetting Liabilities [Line Items]
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet	$ (71,974)	$ (24,505)
Gross Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet	(71,974)	(24,505)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Financial Instruments	71,382	24,505
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Cash Collateral Posted	377	0
Total Net	(215)	0
Interest rate swap contracts
Offsetting Liabilities [Line Items]
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet	(70,290)	(24,505)
Gross Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet	(70,290)	(24,505)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Financial Instruments	70,290	24,505
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Cash Collateral Posted	0	0
Total Net	0	0
TBA Agency Securities
Offsetting Liabilities [Line Items]
Net Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet	(1,684)
Gross Amounts of Liabilities Presented in the Condensed Consolidated Balance Sheet	(1,684)	$ 0
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Financial Instruments	1,092
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet, Cash Collateral Posted	377
Total Net	$ (215)

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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