Share-based Compensation (Summary of Share Options Activities) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014 years
Number of options
Outstanding at beginning of period	11,482,513
Granted	258,500
Exercised	(1,833,657)
Expired	(3,000)
Forfeited	(720,366)
Outstanding at end of period	9,183,990
Vested and exercisable	4,913,833
Vested and expect to vest	16,690,231
Weighted average exercise price per option
Outstanding at beginning of period	$ 10.04
Granted	$ 45.35
Exercised	$ 7.96
Expired	$ 58.49
Forfeited	$ 20.23
Outstanding at end of period	$ 10.57
Vested and exercisable	$ 7.00
Vested and expect to vest	$ 8.32
Weighted average remaining contractual life (Years)
Outstanding at beginning of period	7.55
Outstanding at end of period	6.61
Vested and exercisable	6.09
Vested and expect to vest	6.28
Aggregate intrinsic value (in thousands)
Outstanding at beginning of period	$ 512,964
Outstanding at end of period	257,557
Vested and exercisable	153,647
Vested and expect to vest	$ 502,394

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Weighted average remaining contractual term for option awards outstanding.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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