Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) Share data 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
Accounting Policies [Abstract]
Restricted common shares issued			600
Adjusted amount to correct capitalization interest	$ 224,000
Quarterly dividend paid per Common Share	$ 0.1625	$ 0.1625	$ 0.4875	$ 0.4875
Quarterly dividend paid per Series D Preferred Share	$ 0.578125		$ 1.7344	$ 1.15625