Summary of Significant Accounting Policies - Reconciliation of Earnings Attributable to Common Shares Outstanding for the Basic and Diluted EPS (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Basic
Income from continuing operations	$ 12,167	$ 15,962	$ 23,404	$ 25,690
(Income) loss attributable to non-controlling interest	995	(939)	2,419	435
Preferred dividend on Series D Preferred Shares	(2,787)	(2,786)	(8,360)	(6,498)
Dividend on Restricted Shares	(97)		(211)
Income from continuing operations applicable to Common Shares	10,278	12,237	17,252	19,627
Income (loss) from discontinued operations	(1,434)	85	8,025	594
Allocation of undistributed earnings to Restricted Shares	(9)		(24)
Net income attributable to Common Shares	8,835	12,322	25,253	20,221
Basic Weighted-Average Common Shares	33,076	33,075	33,047	33,064
Income from continuing operations	$ 0.31	$ 0.37	$ 0.52	$ 0.59
Income (loss) from discontinued operations	$ (0.04)		$ 0.24	$ 0.02
Earnings per Common Share - Basic	$ 0.27	$ 0.37	$ 0.76	$ 0.61
Diluted
Income from continuing operations	12,167	15,962	23,404	25,690
(Income) loss attributable to non-controlling interest	995	(939)	2,419	435
Preferred dividend on Series D Preferred Shares	(2,787)	(2,786)	(8,360)	(6,498)
Dividend on Restricted Shares	(97)		(211)
Income from continuing operations applicable to Common Shares	10,278	12,237	17,252	19,627
Income (loss) from discontinued operations	(1,434)	85	8,025	594
Allocation of undistributed earnings to Restricted Shares	(9)		(24)
Net income attributable to Common Shares	$ 8,835	$ 12,322	$ 25,253	$ 20,221
Basic Weighted-Average Common Shares	33,076	33,075	33,047	33,064
Stock options (1)	2	1	2
Restricted shares (2)	70		40
Diluted weighted-average Common Shares	33,148	33,076	33,089	33,064
Income from continuing operations	$ 0.31	$ 0.37	$ 0.52	$ 0.59
Income (loss) from discontinued operations	$ (0.04)		$ 0.24	$ 0.02
Earnings per Common Share - Diluted	$ 0.27	$ 0.37	$ 0.76	$ 0.61