Debt - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended				3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Dec. 31, 2007 Defeased Debt	Mar. 31, 2013 Defeased Debt	Dec. 31, 2012 Defeased Debt	Mar. 31, 2013 Total Outstanding Cdd Debt	Dec. 31, 2012 Total Outstanding Cdd Debt
Debt Disclosure [Line Items]
Total community development district debt	$ 9,100,000	$ 9,200,000				$ 34,600,000	$ 34,800,000
Long term debt	$ 35,752,000	$ 36,062,000	$ 29,300,000	$ 26,676,000	$ 26,818,000
Long term debt, year of balloon payment			2015