Consolidated Statement Of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS:
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 57,190	$ 64,274
Reconciliation of the net increase in equity resulting from operations to net cash provided by (used in) operating activities:
Change in net unrealized (gain) loss on investments and financial derivatives, and foreign currency translation	(10,678)	(4,578)
Net realized (gain) loss on investments, financial derivatives, and foreign currency transactions	(8,115)	(22,552)
Amortization of premiums and accretion of discounts (net)	(6,036)	(15,485)
Purchase of investments	(2,899,745)	(1,763,022)
Proceeds from disposition of investments	2,118,261	1,166,380
Proceeds from principal payments of investments	135,376	145,570
Proceeds from investments sold short	1,429,501	905,142
Repurchase of investments sold short	(1,087,703)	(652,073)
Payments made to open financial derivatives	(18,692)	(11,720)
Proceeds received to close financial derivatives	41,677	35,406
Proceeds received to open financial derivatives	43,471	27,986
Payments made to close financial derivatives	(65,865)	(26,686)
Shares issued in connection with incentive fee payment	309	1,058
Share-based LTIP expense	191	129
(Increase) decrease in assets:
Increase in repurchase agreements	(19,077)	(27,344)
Increase in receivable for securities sold	(363,200)	(299,719)
Increase in due from brokers	(58,926)	(42,415)
Increase in interest and principal receivable	(4,122)	(972)
Increase in other assets	(1,182)	(713)
Increase (decrease) in liabilities:
Decrease in due to brokers	(7,752)	(17,214)
Increase in payable for securities purchased	383,408	173,317
Increase in accounts payable and accrued expenses	440	262
Decrease in incentive fee payable	(1,691)	(5,305)
Increase (decrease) in other payables	0	(396)
Increase in interest and dividends payable	617	768
Increase in base management fee payable	692	444
Net cash used in operating activities	(341,651)	(369,458)
Cash flows provided by (used in) financing activities:
Proceeds from the issuance of shares	188,400	125,600
Contribution from non-controlling interest	1,524	4,664
Offering costs paid	(151)	(350)
Dividends paid	(60,210)	(72,016)
Distributions to non-controlling Interest	(1,099)	0
Principal payments on securitized debt	(144)	(292)
Reverse repurchase agreements, net of repayments	158,966	439,505
Net cash provided by financing activities	287,286	497,111
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(54,365)	127,653
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	183,489	59,084
CASH AND CASH EQUIVALENTS, END OF PERIOD	129,124	186,737
Supplemental disclosure of cash flow information:
Interest paid	7,110	7,217
Shares issued in connection with incentive fee payment (non-cash)	309	1,058
Share-based LTIP awards (non-cash)	191	129
Aggregate TBA trade activity (buys sells) (non-cash)	$ 20,616,947	$ 16,476,137