Consolidated Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (loss)	$ 2,449,000	$ (4,591,000)
Adjustments to reconcile net income (loss) to net cash (used in) provided by operating activities:
Stock based compensation and equity plan amortization	243,000	268,000
Realized and unrealized (gains) losses on mortgage-backed securities	16,308,000	(8,029,000)
Realized and unrealized loss on interest rate swaption	0	(36,000)
Unrealized (gains) losses on interest rate swaps	1,534,000	(21,000)
Gains On TBA Securities	0	1,125,000
Changes in operating assets and liabilities
Accrued interest receivable	(1,676,000)	184,000
Other assets	(417,000)	(350,000)
Accrued interest payable	164,000	32,000
Other liabilities	1,819,000	(498,000)
Due to affiliates	262,000	(26,000)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	17,618,000	(11,900,000)
From mortgage-backed securities investments
Purchases	(1,737,240,000)	(715,281,000)
Sales	1,407,673,000	741,114,000
Principal repayments	73,298,000	51,909,000
Proceeds From Sale Of Federal Home Loan Bank Stock	3,000	3,750,000
Proceeds From Net TBA Settlements	1,119,000	(942,000)
Purchase of interest rate swaptions, net of margin cash received	0	(705,000)
NET CASH USED IN INVESTING ACTIVITIES	(255,147,000)	81,255,000
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from repurchase agreements	11,947,907,000	6,234,852,000
Principal payments on repurchase agreements	(11,691,004,000)	(6,094,176,000)
Payments For Federal Home Loan Bank Advances	0	187,500,000
Cash dividends	(13,869,000)	(9,154,000)
Proceeds From Issuance Of Common Stock	12,793,000	0
NET CASH PROVIDED BY FINANCING ACTIVITIES	255,827,000	(55,978,000)
NET INCREASE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	18,298,000	13,377,000
CASH, CASH EQUIVALENTS AND RESTRICTED CASH, beginning of period	94,425,000	69,959,000
CASH, CASH EQUIVALENTS AND RESTRICTED CASH, end of period	112,723,000	83,336,000
Cash paid during the period for:
Interest	6,551,000	3,288,000
SUPPLEMENTAL DISCLOSURES OF NONCASH FINANCING ACTIVITIES:
Securities acquired settled in later period	0	21,486,000
Securities sold settled in later period	$ 0	$ 132,174,000