Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-Name Staff Accounting Bulletin (SAB)

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Name Accounting Standards Codification

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Share-based Compensation (Narrative of Share Options) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 25, 2006	Apr. 01, 2011
Share options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value per option granted during period	$ 32.61	$ 13.19	$ 6.77
Total intrinsic value of options exercised during period	$ 98,112	$ 138,364	$ 19,486
Allocated share-based compensation expense	16,702	21,921	26,997
Unrecognized share-based compensation expense relating to share options	$ 18,875
Period for recognition of unrecognized share-based compensation expense (in years)	0 years 8 months 23 days
2006 Employee Share Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share options, validity period (in years)				10 years
2006 Employee Share Option Plan [Member] \| Share options [Member] \| Each anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of aggregate number of options will be vested	25.00%
2011 Employee Share Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share options, validity period (in years)					10 years
2011 Employee Share Incentive Plan [Member] \| Share options [Member] \| 12 months after start of vesting period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of aggregate number of options will be vested	20.00%
2011 Employee Share Incentive Plan [Member] \| Share options [Member] \| 24 months after start of vesting period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of aggregate number of options will be vested	20.00%
2011 Employee Share Incentive Plan [Member] \| Share options [Member] \| 36 months after start of vesting period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of aggregate number of options will be vested	30.00%
2011 Employee Share Incentive Plan [Member] \| Share options [Member] \| 48 months after start of vesting period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of aggregate number of options will be vested	30.00%