Consolidated Statements of Cash Flows - USD ($)	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (loss)	$ 22,397,000	$ (6,738,000)
Adjustments to reconcile net income (loss) to net cash (used in) provided by operating activities:
Stock based compensation and equity plan amortization	492,000	364,000
Realized and unrealized (gains) losses on mortgage-backed securities	(10,134,000)	10,102,000
Realized and unrealized loss on interest rate swaption	(36,000)	1,217,000
Unrealized (gains) losses on interest rate swaps	792,000	0
Gains On TBA Securities	2,385,000	(24,000)
Changes in operating assets and liabilities
Accrued interest receivable	(967,000)	(1,973,000)
Other assets	(93,000)	(488,000)
Accrued interest payable	1,010,000	(176,000)
Other liabilities	(204,000)	9,000
Due to affiliates	15,000	89,000
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	14,073,000	2,382,000
From mortgage-backed securities investments
Purchases	(2,184,709,000)	(2,106,110,000)
Sales	1,717,612,000	1,364,754,000
Principal repayments	178,460,000	166,910,000
Proceeds From Sale Of Federal Home Loan Bank Stock	3,750,000	0
Increase in restricted cash	(4,151,000)	(3,444,000)
Proceeds From Net TBA Settlements	(2,145,000)	24,000
Purchase of interest rate swaptions, net of margin cash received	(705,000)	1,364,000
NET CASH USED IN INVESTING ACTIVITIES	(290,478,000)	(579,230,000)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from repurchase agreements	22,443,458,000	13,608,591,000
Principal payments on repurchase agreements	(21,944,174,000)	(13,101,943,000)
Payments For Federal Home Loan Bank Advances	187,500,000	0
Cash dividends	(28,864,000)	(29,598,000)
Proceeds From Issuance Of Common Stock	47,116,000	83,275,000
PaymentsForRepurchaseOfCommonStock	0	9,512,000
NET CASH PROVIDED BY FINANCING ACTIVITIES	330,036,000	550,813,000
NET INCREASE IN CASH AND CASH EQUIVALENTS	53,631,000	(26,035,000)
CASH AND CASH EQUIVALENTS, beginning of the period	57,229,000	93,137,000
CASH AND CASH EQUIVALENTS, end of the period	110,860,000	67,102,000
Cash paid during the period for:
Interest	9,619,000	5,076,000
SUPPLEMENTAL DISCLOSURES OF NONCASH FINANCING ACTIVITIES:
Securities acquired settled in later period	72,343,000	92,325,000
Securities sold settled in later period	$ 27,509,000	$ 87,558,000