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Stock-Based Compensation - Number of Shares Available for Issuance (Details) - USD ($) $ / shares in Units, $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2014 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Number of shares available for issuance |  |  |  |  |
Outstanding number of shares available for issuance at the beginning of the year (in shares) |  | 20,217,000 | 2,738,000 | 4,648,000 |
Addition (in shares) |  |  | 21,684,000 | 1,000,000 |
Granted (in shares) |  | (1,917,000) | (4,851,000) | (2,951,000) |
Cancelled/expired/forfeited (in shares) |  | 578,000 | 646,000 | 41,000 |
Outstanding number of shares available for issuance at the end of the year (in shares) |  | 18,878,000 | 20,217,000 | 2,738,000 | 4,648,000
Aggregate Intrinsic Value |  |  |  |  |
Fair value per ordinary share (in dollars per share) |  | $ 40.60 | $ 19.50 | $ 14.24 |
2014 Plan |  |  |  |  |
Number of shares available for issuance |  |  |  |  |
Addition (in shares) | 1,000,000 |  |  |  |
Stock options |  |  |  |  |
Options Outstanding |  |  |  |  |
Outstanding at the beginning of the year (in shares) |  | 6,303,000 | 14,330,000 | 18,561,000 |
Exercise (in shares) |  | (3,625,000) | (7,309,000) | (3,697,000) |
Cancelled/expired/forfeited (in shares) |  | (91,000) | (718,000) | (534,000) |
Outstanding at the end of the year (in shares) |  | 2,587,000 | 6,303,000 | 14,330,000 | 18,561,000
Vested and expected to vest at the end of the year (in shares) |  | 2,572,000 | 6,237,000 |  |
Exercisable at the end of the year (in shares) |  | 2,433,000 | 5,649,000 |  |
Weighted Average Exercise Price |  |  |  |  |
Outstanding at the beginning of the year (in dollars per share) |  | $ 1.26 | $ 1.28 | $ 1.17 |
Exercise (in dollars per share) |  | 1.10 | 1.11 | 0.52 |
Cancelled/expired/forfeited (in dollars per share) |  | 3.37 | 3.22 | 2.84 |
Outstanding at the end of the year (in dollars per share) |  | 1.41 | 1.26 | $ 1.28 | $ 1.17
Vested and expected to vest at the end of the year (in dollars per share) |  | 1.40 | 1.24 |  |
Exercisable at the end of the year (in dollars per share) |  | $ 1.28 | $ 1.01 |  |
Weighted Average Remaining Contractual Life (in years) |  |  |  |  |
Outstanding at the end of the year |  | 1 year 7 months 6 days | 2 years 4 months 24 days | 3 years 2 months 12 days | 4 years 3 months 18 days
Vested and expected to vest at the end of the year |  | 1 year 7 months 6 days | 2 years 4 months 24 days |  |
Exercisable at the end of the year |  | 1 year 4 months 24 days | 2 years 2 months 12 days |  |
Aggregate Intrinsic Value |  |  |  |  |
Outstanding at the end of the year |  | $ 101,403 | $ 114,975 | $ 185,684 | $ 239,975
Vested and expected to vest at the end of the year |  | 100,819 | 113,909 |  |
Exercisable at the end of the year |  | 95,678 | 104,473 |  |
Total intrinsic value of options exercised |  | 129,300 | 106,200 | 65,700 |
Cash received from the exercise of stock option |  | 4,200 | 7,800 | $ 1,500 |
Unrecognized compensation cost |  | $ 1,100 | $ 3,900 |  |
Weighted-average period of unrecognized compensation cost |  | 9 months 18 days |  |  |
Stock options | 2014 Plan |  |  |  |  |
Options Outstanding |  |  |  |  |
Granted (in shares) |  | 0 | 0 | 0 |
Restricted share units |  |  |  |  |
Number of shares available for issuance |  |  |  |  |
Restricted shares units granted (in shares) |  | 1,900,000 | 4,900,000 | 3,000,000 |

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- Definition Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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