Consolidated Statement Of Changes In Equity - USD ($) $ in Thousands		Total		Parent [Member]	Noncontrolling Interest [Member]
Stockholders' Equity Attributable to Parent at Dec. 31, 2014				$ 782,155
Stockholders' Equity Attributable to Noncontrolling Interest at Dec. 31, 2014					$ 6,389
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2014		$ 788,544
CHANGE IN SHAREHOLDERS’ EQUITY RESULTING FROM OPERATIONS
Net investment income		35,197
Net realized gain (loss) on investments, financial derivatives, and foreign currency transactions		11,190
Change in net unrealized gain (loss) on investments, financial derivatives, and foreign currency translation		(13,747)
Net Income (Loss) Attributable to Parent		32,413		32,413
Net Income (Loss) Attributable to Noncontrolling Interest		227			227
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest		32,640
CHANGE IN EQUITY RESULTING FROM TRANSACTIONS
Contributions from non-controlling interests		1,430			1,430
Dividends	[1]	(44,318)	[2]	(44,044)	(274)
Distributions to non-controlling interest		(1,410)			(1,410)
Adjustment to non-controlling interest		0		0	0
Shares repurchased		0		0
Share-based LTIP awards		196		195	1
Net increase (decrease) in equity from transactions		(44,102)		(43,849)	(253)
Net increase (decrease) in equity		(11,462)		(11,436)	(26)
Stockholders' Equity Attributable to Parent at Jun. 30, 2015				770,719
Stockholders' Equity Attributable to Noncontrolling Interest at Jun. 30, 2015					6,363
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Jun. 30, 2015		777,082
Stockholders' Equity Attributable to Parent at Dec. 31, 2015		732,049		732,049
Stockholders' Equity Attributable to Noncontrolling Interest at Dec. 31, 2015		6,903			6,903
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2015		738,952
CHANGE IN SHAREHOLDERS’ EQUITY RESULTING FROM OPERATIONS
Net investment income		20,343
Net realized gain (loss) on investments, financial derivatives, and foreign currency transactions		(14,272)
Change in net unrealized gain (loss) on investments, financial derivatives, and foreign currency translation		(24,255)
Net Income (Loss) Attributable to Parent		(18,215)		(18,215)
Net Income (Loss) Attributable to Noncontrolling Interest		31			31
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest		(18,184)
CHANGE IN EQUITY RESULTING FROM TRANSACTIONS
Contributions from non-controlling interests		684			684
Dividends	[1]	(33,616)	[2]	(33,404)	(212)
Distributions to non-controlling interest		(2,228)			(2,228)
Adjustment to non-controlling interest		0		(9)	9
Shares repurchased		(6,624)		(6,624)
Share-based LTIP awards		199		198	1
Net increase (decrease) in equity from transactions		(41,585)		(39,839)	(1,746)
Net increase (decrease) in equity		(59,769)		(58,054)	(1,715)
Stockholders' Equity Attributable to Parent at Jun. 30, 2016		673,995		$ 673,995
Stockholders' Equity Attributable to Noncontrolling Interest at Jun. 30, 2016		5,188			$ 5,188
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Jun. 30, 2016		$ 679,183

[1] For the six month periods ended June 30, 2016 and 2015, dividends totaling $1.00 and $1.30, respectively, per common share and convertible unit outstanding, were declared and paid.

[2] The Company pays quarterly dividends in arrears, so a portion of the dividends paid in each calendar year relate to the prior year's earnings.