Investment Activity (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended				3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 TRA Preferred Stock	Sep. 30, 2012 TRA Preferred Stock	Sep. 30, 2011 TRA Preferred Stock	Jun. 30, 2011 TRA Preferred Stock	Dec. 31, 2010 TRA Preferred Stock	Sep. 30, 2012 Scarborough	Sep. 30, 2011 Scarborough	Sep. 30, 2012 Scarborough	Sep. 30, 2011 Scarborough
Schedule Of Equity And Other Investments [Line Items]
Beginning balance, equity and other investments	$ 13,648	$ 17,256	$ 14,913	$ 18,385
Beginning balance, cost method investments			1,703		1,703	1,703	5,180	5,180	5,180
Beginning balance, equity method investments			13,210							11,945	12,076	13,210	13,205
Investment in affiliate (loss) income	(2,364)	(2,290)	671	631						(2,364)	(2,290)	671	631
Distributions from investee	(2,075)	(2,150)	(6,375)	(6,200)						(2,075)	(2,150)	(6,375)	(6,200)
Proceeds from sale of investment	(1,466)		(1,466)		(1,466)	(1,466)
Receivable from sale of investment	(214)		(214)		(214)	(214)
Loss on sale of investment	(23)		(23)		(23)	(23)
Ending balance at September 30, equity and other investments	7,506	12,816	7,506	12,816
Ending balance at September 30, cost method investments							5,180	5,180	5,180
Ending balance at September 30, equity method investments	$ 7,506		$ 7,506							$ 7,506	$ 7,636	$ 7,506	$ 7,636