Share-based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

Share-based Compensation [Abstract]

Fair Value of Share Options, Valuation Assumptions

	Year ended December 31,
	2012	2013	2014
Risk-free interest rate	2.83% - 3.35%	3.40% - 4.02%	3.96%~4.61%
Expected life (years)	6.35	6.35	5.85~6.35
Volatility	46.98% - 74%	46.04% - 46.68%	44.28%~46.02%
Dividend yield	-	-	-

Summary of Share Options Activities

				Weighted average		Weighted average		Aggregate
				exercise price		remaining contractual		intrinsic value
	Number of options			per option		life (Years)		(in thousands)
Outstanding at December 31, 2013		11,482,513		$	10.04		7.55		512,964
Granted		258,500			45.35
Exercised		(1,833,657	)		7.96
Expired		(3,000	)		58.49
Forfeited		(720,366	)		20.23
Outstanding at December 31, 2014		9,183,990		$	10.57		6.61		257,557
Vested and exercisable at December 31, 2014		4,913,833			7.00		6.09		153,647
Vested and expect to vest at December 31, 2014		16,690,231			8.32		6.28		502,394

Summary of Nonvested Shares Activities

				Weighted average
				fair value per
	Number of			nonvested share
	nonvested shares			at the grant date
Outstanding at December 31, 2013		10,070,794		$	15.44
Granted		2,734,139			56.27
Vested		(3,086,753	)		12.79
Forfeited		(1,174,065	)		33.32
Outstanding at December 31, 2014		8,544,115		$	26.85
Vested and to be transferred to grantees at December 31, 2014		21,503,321
Vested and expect to vest at December 31, 2014		31,574,115