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Equity - Incentive Equity Awards - Additional Information (Detail) - USD ($) $ in Thousands							6 Months Ended
	May 14, 2018	Mar. 12, 2018	Feb. 01, 2018	Oct. 02, 2017	May 15, 2017	Feb. 01, 2017	Jun. 30, 2018	Jun. 30, 2017
Stockholders Equity Note [Line Items]
Stock options, outstanding							25,281,555
Shares issued, exercise of stock options							956,232	221,345
Proceeds from exercise of stock options, net of transaction costs							$ 1,826	$ 396
Restricted Stock Units (RSUs)
Stockholders Equity Note [Line Items]
Restricted stock units, outstanding							12,248,642
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	190,034		1,305,575		91,504	1,575,000
Stock units, Vesting Period	3 years		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	286,536		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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