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Equity - Incentive Equity Awards - Additional Information (Detail) - USD ($) $ in Thousands |  |  |  |  |  | 3 Months Ended
--- | --- | --- | --- | --- | --- | ---
Mar. 12, 2018 | Feb. 01, 2018 | Oct. 02, 2017 | May 15, 2017 | Feb. 01, 2017 | Mar. 31, 2018 | Mar. 31, 2017
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |
Stock options, outstanding |  |  |  |  |  | 25,702,956 |
Shares issued, exercise of stock options |  |  |  |  |  | 782,553 | 172,027
Proceeds from exercise of stock options, net of transaction costs |  |  |  |  |  | $ 1,548 | $ 296
Restricted Stock Units (RSUs) |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |
Restricted stock units, outstanding |  |  |  |  |  | 12,420,208 |
Percentage of outstanding shares on a fully diluted basis |  |  |  |  |  | 3.00% |
Restricted Stock Units (RSUs) | Stock Incentive Plan 2011 |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |
Stock units, Granted |  | 1,305,575 |  | 91,504 | 1,575,000 |  |
Stock units, Vesting Period |  | 3 years |  | 3 years | 3 years |  |
Settlement of shares, related to the vesting of RSUs |  |  |  |  | 989,000 |  |
Restricted Stock Units (RSUs) | Stock Incentive Plan 2011 | Vesting Period |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |
Stock units, Granted | 970,000 |  | 220,000 | 2,310,000 |  |  |
Stock units, Vesting Period |  |  |  | 3 years |  |  |
Restricted Stock Units (RSUs) | Stock Incentive Plan 2011 | Vest over a three year period |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |
Shares issued, related to the vesting of RSUs |  |  |  |  |  | 506,679 |
Treasury shares for settlement of employee tax obligations |  |  |  |  |  | 183,828 |
Stock Options |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |
Percentage of outstanding shares on a fully diluted basis |  |  |  |  |  | 7.00% |
Stock Options | Stock Incentive Plan 2011 |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |
Stock options, Granted |  | 2,205,075 |  | 131,575 | 2,642,500 |  |
Stock units, Vesting Period |  | 4 years |  |  | 4 years |  |

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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=96867065&loc=SL79508275-113901 + Details
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