Consolidated Statement Of Changes In Equity - USD ($) $ in Thousands		Total		Parent [Member]	Noncontrolling Interest [Member]
Stockholders' Equity Attributable to Parent at Dec. 31, 2015				$ 732,049
Stockholders' Equity Attributable to Noncontrolling Interest at Dec. 31, 2015					$ 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
Stockholders' Equity Attributable to Noncontrolling Interest at Jun. 30, 2016					5,188
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Jun. 30, 2016		679,183
Stockholders' Equity Attributable to Parent at Dec. 31, 2016		637,661		637,661
Stockholders' Equity Attributable to Noncontrolling Interest at Dec. 31, 2016		7,116			7,116
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2016		644,777
CHANGE IN SHAREHOLDERS’ EQUITY RESULTING FROM OPERATIONS
Net investment income		20,207
Net realized gain (loss) on investments, financial derivatives, and foreign currency transactions		(6,178)
Change in net unrealized gain (loss) on investments, financial derivatives, and foreign currency translation		7,142
Net Income (Loss) Attributable to Parent		20,342		20,342
Net Income (Loss) Attributable to Noncontrolling Interest		829			829
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest		21,171
CHANGE IN EQUITY RESULTING FROM TRANSACTIONS
Contributions from non-controlling interests		11,321			11,321
Dividends	[1]	(29,579)	[2]	(29,388)	(191)
Distributions to non-controlling interest		(8,050)			(8,050)
Adjustment to non-controlling interest		0		(4)	4
Shares repurchased		(2,868)		(2,868)
Share-based LTIP awards		189		188	1
Net increase (decrease) in equity from transactions		(28,987)		(32,072)	3,085
Net increase (decrease) in equity		(7,816)		(11,730)	3,914
Stockholders' Equity Attributable to Parent at Jun. 30, 2017		625,931		$ 625,931
Stockholders' Equity Attributable to Noncontrolling Interest at Jun. 30, 2017		11,030			$ 11,030
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Jun. 30, 2017		$ 636,961

[1] For the six month periods ended June 30, 2017 and 2016, dividends totaling $0.90 and $1.00 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.