Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net Income	$ 47,704	$ 27,724	$ 106,013	$ 110,141
Other comprehensive income (loss):
Reclassification adjustment for realized (gain) loss on sale of available for sale Agency Securities	31,136	(891)	89,055	10,723
Reclassification adjustment for other than temporary impairment of available for sale Agency Securities	0	72	12,090	10,410
Net unrealized gain (loss) on available for sale Agency Securities	(58,270)	11,887	(253,267)	33,182
Other comprehensive income (loss)	(27,134)	11,068	(152,122)	54,315
Comprehensive Income (Loss)	$ 20,570	$ 38,792	$ (46,109)	$ 164,456

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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