Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ (249,905)	$ (105,966)	$ 181,154
Other comprehensive income (loss):
Reclassification adjustment for realized (gain) loss on sale of available for sale Agency Securities	(9,611)	152,950	8,486
Reclassification adjustment for other than temporary impairment of available for sale Agency Securities	0	12,090	13,707
Net unrealized gain (loss) on available for sale Agency Securities	408,954	(188,799)	(13,170)
Other comprehensive income (loss)	399,343	(23,759)	9,023
Total Comprehensive Income (Loss)	$ 149,438	$ (129,725)	$ 190,177

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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