Property and Equipment, Net (Detail) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Depreciation	$ 2,600,000	$ 1,700,000	$ 5,200,000	$ 2,800,000
Impairments included in discontinued operations			0	1,988,000
Loss From Discontinued Operations, Net of Taxes [Member]
Impairments included in discontinued operations		$ 100,000		$ 100,000