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Percentage of performance based grants that were achieved.

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Share based compensation arrangement by share based payment award estimated forfeiture rate.

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The number of share options granted during the period for which vesting is contingent upon company corporate goals.

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities.

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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.

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Unrecognized cost of unvested share-based compensation awards.

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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.

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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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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.

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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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Gross number of share options (or share units) granted during the period.

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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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Number of options outstanding, including both vested and non-vested options.

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The increase or decrease in number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding, including vested options.

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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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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Stock-Based Compensation - Additional Information (Detail)		12 Months Ended
	Jan. 01, 2017 shares	Dec. 31, 2016 USD ($) Milestone $ / shares shares	Dec. 31, 2015 USD ($) Milestone $ / shares shares	Dec. 31, 2014 USD ($) $ / shares	Jul. 02, 2014 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of options outstanding		4,891,922
Share based compensation granted under plan vest period		4 years
Share based compensation, vest period		1 year
Share based compensation, term of plan		10 years
Stock-based compensation expense \| $		$ 23,020,000	$ 15,240,000	$ 2,512,000
Milestone expense \| $		$ 0
Weighted average grant date fair value per share \| $ / shares		$ 24.97	$ 34.08	$ 14.33
Share option, forfeiture rates		9.58%	10.00%	10.00%
Non-employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation, term of plan		10 years
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grant		1,454,568
Total number of options outstanding		4,231,807	3,002,809
Total unrecognized stock-based compensation expense \| $		$ 43,600,000
Weighted average period of unrecognized compensation costs		2 years 9 months 7 days
Total fair value of options vested \| $		$ 24,100,000	$ 9,200,000	$ 1,000,000
Intrinsic value of options exercised \| $		$ 4,600,000	$ 28,400,000	$ 2,400,000
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grant		245,872
Total unrecognized stock-based compensation expense \| $		$ 5,200,000
Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation, vesting percentage		25.00%
2011 Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grant		0
2016 Inducement Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grant		0
2014 Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for issuance under stock option plan		660,115
Percentage of increase on issued and outstanding shares of Common stock		4.00%
Milestones achieved \| Milestone		1	1
Percentage of performance based grants that were achieved		50.00%
2014 Stock Option Plan [Member] \| Milestone One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance based grants that were achieved			35.00%
2014 Stock Option Plan [Member] \| Milestone Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance based grants that were achieved			30.00%
2014 Stock Option Plan [Member] \| Performance Milestone [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options with performance-based criteria		74,039	497,100
Stock-based compensation expense \| $		$ 5,000,000	$ 4,800,000
2014 Stock Option Plan [Member] \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares annual increase added to plan	1,488,886
2014 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense \| $		$ 200,000	$ 100,000
Shares of common stock initially authorized for issuance under this plan					282,000
Number of shares issued under the plan		14,351
Accrued expenses \| $		$ 67,000