CONSOLIDATED STATEMENTS OF EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Parent [Member]	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Distributions in Excess of Net Income [Member]	Noncontrolling Interest [Member]	Total
Balance at Dec. 31, 2011	$ 466,748	$ 38,500	$ 303	$ 507,343	$ 672,743	$ 199	$ (752,340)	$ 1,962	$ 468,710
Balance (in shares) at Dec. 31, 2011		2,000,000	30,346,000
Equity activity
Reclassification adjustment	(47)					(47)			(47)
Stock option exercises	1,926		1	1,925					1,926
Stock option exercises (in shares)			85,000
Issue restricted stock			1	(1)
Issue restricted stock (in shares)			90,000
Net income	51,290				51,290			37	51,327
Vested stock options	10			10					10
Vested restricted stock	1,809			1,809					1,809
Non-controlling interests conversion	(850)			(850)				(1,914)	(2,764)
Non-controlling interests conversion (in shares)			23,000
Non-controlling interests preferred return								(78)	(78)
Preferred stock dividends	(3,273)						(3,273)		(3,273)
Common stock cash distributions ($2.04, $1.91 and $1.79 per share for the year ended 2014, 2013 and 2012, respectively)	(54,512)						(54,512)		(54,512)
Balance at Dec. 31, 2012	463,101	38,500	305	510,236	724,033	152	(810,125)	7	463,108
Balance (in shares) at Dec. 31, 2012		2,000,000	30,544,000
Equity activity
Reclassification adjustment	(35)					(35)			(35)
Stock option exercises	523			523					523
Stock option exercises (in shares)			22,000
Issuance of common stock	175,598		42	175,556					175,598
Issuance of common stock (in shares)			4,152,000
Issue restricted stock (in shares)			35,000
Net income	57,815				57,815				57,815
Vested restricted stock	2,591			2,591					2,591
Non-controlling interests preferred return								(7)	(7)
Preferred stock dividends	(3,272)						(3,272)		(3,272)
Common stock cash distributions ($2.04, $1.91 and $1.79 per share for the year ended 2014, 2013 and 2012, respectively)	(63,631)						(63,631)		(63,631)
Other	(252)			(252)					(252)
Other (in shares)			(7,000)
Balance at Dec. 31, 2013	632,438	38,500	347	688,654	781,848	117	(877,028)		632,438
Balance (in shares) at Dec. 31, 2013		2,000,000	34,746,000
Equity activity
Reclassification adjustment	(35)					(35)			(35)
Stock option exercises	1,071		1	1,070					1,071
Stock option exercises (in shares)			45,000
Issuance of common stock	24,644		6	24,638					24,644
Issuance of common stock (in shares)			600,000
Issue restricted stock			1	(1)
Issue restricted stock (in shares)			95,000
Net income	73,399				73,399				73,399
Vested stock options	12			12					12
Vested restricted stock	3,241			3,241					3,241
Preferred stock dividends	(3,273)						(3,273)		(3,273)
Common stock cash distributions ($2.04, $1.91 and $1.79 per share for the year ended 2014, 2013 and 2012, respectively)	(71,158)						(71,158)		(71,158)
Other	(218)			(218)					(218)
Other (in shares)			(6,000)
Balance at Dec. 31, 2014	$ 660,121	$ 38,500	$ 355	$ 717,396	$ 855,247	$ 82	$ (951,459)		$ 660,121
Balance (in shares) at Dec. 31, 2014		2,000,000	35,480,000