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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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Percentage of outstanding common shares and preferred shares on fully diluted basis.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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