Stock-Based Compensation - Stock Option Activity under EIP (Executive Incentive Plan) (Detail) (USD $)	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance	2,524,500	2,544,000
Granted	20,920,000	160,000
Canceled	(244,500)	(79,500)
Exercised	1,892,578	58,000
Balance	23,078,300	2,566,500
Balance	27,434,083	333,447
Granted	(20,920,000)	(160,000)
Canceled	244,500	79,500
Exercised
Balance	6,758,583	252,947
Balance	$ 3.38	$ 3.00
Granted	$ 3.44	$ 10.60
Canceled	$ 4.86	$ 5.63
Exercised	$ 1.81	$ 2.20
Balance	$ 3.43	$ 3.41