Description of corporate income tax rate.

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Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Forfeiture rate.

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- Definition

Summary of Significant Accounting Policies.

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- Definition

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

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- Definition

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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- Definition

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

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No definition available.

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- Definition

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

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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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- Definition

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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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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Summary of Significant Accounting Policies (Details Textual) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Dec. 22, 2017 USD ($)	Mar. 31, 2018 USD ($) Segment $ / shares	Mar. 31, 2017 $ / shares	Dec. 31, 2017 Segment $ / shares shares	Dec. 31, 2016 $ / shares
Summary of Significant Accounting Policies (Textual)
Number of operating segments \| Segment		2		2
Weighted average exercise price, granted				$ 1.54	$ 3.90
U.S. corporate income tax rate, description	U.S. corporate income tax rate from 35.0% to 21.0% effective January 1, 2018.
Deferred tax assets \| $	$ 14	$ 14
Minimum [Member]
Summary of Significant Accounting Policies (Textual)
Intangible assets, estimated useful life		11 years		11 years
Risk-free interest rate			1.72%
Maximum [Member]
Summary of Significant Accounting Policies (Textual)
Intangible assets, estimated useful life		16 years		16 years
Risk-free interest rate			1.81%
Directors Upon Re-election [Member]
Summary of Significant Accounting Policies (Textual)
Stock option, expiration period		1 year		1 year
Permanent Employees or Director [Member]
Summary of Significant Accounting Policies (Textual)
Stock option, expiration period		10 years		10 years
Terminated Employees or Directors [Member]
Summary of Significant Accounting Policies (Textual)
Stock option, expiration period		3 months		3 months
Stock Option [Member]
Summary of Significant Accounting Policies (Textual)
Weighted average exercise price, outstanding		$ 7.16	$ 12.70	$ 7.15
Dividend yield			0.00%	0.00%	0.00%
Expected term			4 years	4 years	4 years
Volatility rate			84.00%
Forfeiture rate			12.00%	12.00%	12.00%
Stock option vesting, description		Stock options issued to employees generally vest 25% on the grant date, then 25% each subsequent year for a period of three years.		Stock options issued to employees generally vest 25% on the grant date, then 25% each subsequent year for a period of three years.
Weighted average exercise price, granted			$ 2.67	$ 2.24	$ 5.30
Stock options issued \| shares				476,100
Stock Option [Member] \| Minimum [Member]
Summary of Significant Accounting Policies (Textual)
Volatility rate				90.00%	84.00%
Risk-free interest rate				1.60%	0.96%
Stock Option [Member] \| Maximum [Member]
Summary of Significant Accounting Policies (Textual)
Volatility rate				93.00%	121.00%
Risk-free interest rate				2.02%	1.70%
Warrant [Member]
Summary of Significant Accounting Policies (Textual)
Weighted average exercise price, outstanding		$ 4.38	$ 4.13	$ 4.38