Consolidated Statement Of Changes In Equity (USD $) In Thousands, unless otherwise specified		Total		Parent [Member]	Noncontrolling Interest [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2012		$ 506,355
Stockholders' Equity Attributable to Noncontrolling Interest at Dec. 31, 2012					0
Stockholders' Equity Attributable to Parent at Dec. 31, 2012				506,355
CHANGE IN SHAREHOLDERS’ EQUITY RESULTING FROM OPERATIONS
Net investment income		22,737
Net realized gain (loss) on investments, financial derivatives, and foreign currency transactions		18,264
Total Net Unrealized Gain Loss On Investments, Financial derivatives, and Foreign currency translation		11,450
Net Income (Loss) Attributable to Parent		51,935		51,935
Net Income (Loss) Attributable to Noncontrolling Interest		516			516
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest		52,451
CHANGE IN EQUITY RESULTING FROM TRANSACTIONS
Proceeds from the issuance of shares		125,600		125,600
Shares issued in connection with incentive fee payment		941		941
Noncontrolling Interest, Increase from Sale of Parent Equity Interest		4,664			4,664
Dividends	[1]	(51,976)	[2]	(51,491)	(485)
Distributions to non-controlling interest		0			0
Adjustments to non-controlling interests		0		0	0
Offering costs		(262)		(262)
Share-based LTIP awards		85		84	1
Net increase (decrease) in equity from transactions		79,052		74,872	4,180
Net increase in equity		131,503		126,807	4,696
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Jun. 30, 2013		637,858
Stockholders' Equity Attributable to Noncontrolling Interest at Jun. 30, 2013					4,696
Stockholders' Equity Attributable to Parent at Jun. 30, 2013				633,162
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2013		626,049
Stockholders' Equity Attributable to Noncontrolling Interest at Dec. 31, 2013		5,648			5,648
Stockholders' Equity Attributable to Parent at Dec. 31, 2013		620,401		620,401
CHANGE IN SHAREHOLDERS’ EQUITY RESULTING FROM OPERATIONS
Net investment income		27,087
Net realized gain (loss) on investments, financial derivatives, and foreign currency transactions		15,093
Total Net Unrealized Gain Loss On Investments, Financial derivatives, and Foreign currency translation		1,862
Net Income (Loss) Attributable to Parent		43,582		43,582
Net Income (Loss) Attributable to Noncontrolling Interest		460			460
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest		44,042
CHANGE IN EQUITY RESULTING FROM TRANSACTIONS
Proceeds from the issuance of shares		0		0
Shares issued in connection with incentive fee payment		309		309
Noncontrolling Interest, Increase from Sale of Parent Equity Interest		1,201			1,201
Dividends	[1]	(40,140)	[2]	(39,814)	(326)
Distributions to non-controlling interest		(465)			(465)
Adjustments to non-controlling interests		0		(497)	497
Offering costs		0		0
Share-based LTIP awards		127		126	1
Net increase (decrease) in equity from transactions		(38,968)		(39,876)	908
Net increase in equity		5,074		3,706	1,368
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Jun. 30, 2014		631,123
Stockholders' Equity Attributable to Noncontrolling Interest at Jun. 30, 2014		7,016			7,016
Stockholders' Equity Attributable to Parent at Jun. 30, 2014		$ 624,107		$ 624,107

[1] For the six month periods ended June 30, 2014 and 2013, dividends totaling $1.54 and $2.29, 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.