Acquisition-date fair value of assumed Zalicus equity awards attributable to precombination services

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Represents the amount of reduced share based compensation expense allocated during the period due to modification of an award.

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Share-based compensation arrangement by share-based payment award, award remaining vesting period.

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Under the evergreen provision of the 2015 Equity Incentive plan, this represents the annual increase to the shares of common stock available for issuance.

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Under the evergreen provision of the 2015 Equity Incentive Plan, this represents the annual percentage increase in shares available for issuance under the percentage alternative.

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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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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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Unrecognized cost of unvested options awarded to employees as compensation.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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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 estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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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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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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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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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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- Definition

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

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No definition available.

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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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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of 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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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	12 Months Ended
	Jul. 15, 2014	Jul. 15, 2014	Aug. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Jun. 04, 2015	Apr. 01, 2014	Dec. 31, 2011
Stock-Based Compensation
Stock-based compensation expense				$ 3,470	$ 1,719
Reduced share based compensation expense				$ 100
Remaining vesting period				3 years
Weighted average fair value
Cash received from exercise of stock options				$ 355	$ 90
Zalicus
Stock-Based Compensation
Acquisition-date fair value of assumed Zalicus equity awards attributable to precombination services		$ 220
Weighted-average assumptions
Risk-free interest rate		1.91%
Expected volatility		66.02%
Minimum \| Zalicus
Weighted-average assumptions
Expected term	1 month 6 days
Maximum \| Zalicus
Weighted-average assumptions
Expected term	6 years
Employees of acquirees \| Zalicus
Stock-Based Compensation
Stock-based compensation expense				355
Non employees of acquirees \| Zalicus
Stock-Based Compensation
Stock-based compensation expense				$ 303
Stock Options
Stock-Based Compensation
Vesting Period				4 years
Vesting percentage in first anniversary				25.00%
Maximum term of a stock option				10 years
Number of Options
Outstanding at the beginning of the period				1,652,882
Granted				2,269,247
Exercised				(130,920)
Cancelled				(177,782)
Outstanding at the end of the period				3,613,427	1,652,882
Vested and expected to vest at end of period				3,438,732
Exercisable at end of period				699,459
Weighted-Average Exercise Price
Outstanding at the beginning of the period				$ 10.03
Granted				7.50
Exercised				2.71
Cancelled				7.83
Outstanding at the end of the period				8.81	$ 10.03
Vested and expected to vest at end of period				8.90
Exercisable at end of period				$ 14.73
Weighted-Average Remaining Contractual Term
Outstanding at end of period				8 years 9 months 18 days	8 years 10 months 24 days
Vested and expected to vest at end of period				8 years 9 months 18 days
Exercisable at end of period				7 years 8 months 12 days
Aggregate Intrinsic Value
Outstanding at end of period				$ 485	$ 1,628
Vested and expected to vest at end of period				482
Exercisable at end of period				316
Total intrinsic value of options exercised				$ 547	$ 71
Weighted average fair value
Weighted average grant-date fair value of options granted during the period				$ 4.86
Cash received from exercise of stock options				$ 355
Unrecognized stock-based compensation expense
Unrecognized stock-based compensation expense				$ 11,284
Unrecognized stock-based compensation expense, Recognition period				3 years 1 month 6 days
Weighted-average assumptions
Expected term				6 years	6 years
Expected dividend yield				0.00%	0.00%
Stock Options \| Minimum
Weighted-average assumptions
Risk-free interest rate				1.48%	1.80%
Expected volatility				61.40%	63.96%
Stock Options \| Maximum
Weighted-average assumptions
Risk-free interest rate				1.96%	2.09%
Expected volatility				89.05%	66.07%
2004 Plan
Stock-Based Compensation
Increase in number of shares available for issuance			3,000,000
Shares available for issuance				0
2011 Plan
Stock-Based Compensation
Authorized number of shares							1,504,752	740,470
2015 Plan
Stock-Based Compensation
Authorized number of shares						1,700,000
Shares available for issuance				394,402
Annual increase to shares available for issuance, minimum alternative				1,000,000
Annual increase to shares available for issuance, percentage alternative				4.00%