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Share based compensation arrangement by share based payment award options exercises in period intrinsic value per share.

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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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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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Date the equity-based award expires, in CCYY-MM-DD format.

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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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No definition available.

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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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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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No definition available.

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

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

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Value of stock issued as a result of the exercise of stock options.

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Stock Options and Warrants - Stock Options - Additional Information (Detail)	2 Months Ended	3 Months Ended	12 Months Ended
	Dec. 31, 2009 shares	Mar. 31, 2018 USD ($) Executive $ / shares shares	Dec. 31, 2017 shares	Dec. 31, 2010 shares	Dec. 31, 2006 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to stock options \| $		$ 2,500,000
Unrecognized compensation cost related to unvested shares expected to be recognized, weighted-average period		2 years 2 months 12 days
2006 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiry of options		10 years
Stock options expiration date		Nov. 16, 2016
Options granted to employees, directors and consultants		0
2006 Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options that may be granted					100,000
2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiry of options		10 years
2010 Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options that may be granted				3,700,000
Outside Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiry of options		10 years
Options granted to employees, directors and consultants	68,384
Award vesting terms		50 months
2006 Plan and 2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted to employees, directors and consultants		1,030,108	1,145,568
Stock options exercised		82,501
Weighted average exercise price per share of options exercised \| $ / shares		$ 1.09
2006 Plan and 2010 Plan [Member] \| Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of executives \| Executive		2
Stock options exercised		82,501
Weighted average exercise price per share of options exercised \| $ / shares		$ 1.09
Total exercise price of options exercised \| $		$ 90,171
Intrinsic value of options exercised \| $		$ 34,406
Intrinsic value of options exercised per share \| $ / shares		$ 0.42
2006 Plan and 2010 Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiry of options		10 years