Represents the number of geographic segments in which the entity operates.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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- Definition

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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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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Summary of Significant Accounting Policies (Details)	1 Months Ended	12 Months Ended
Summary of Significant Accounting Policies (Details)	Sep. 12, 2017	Dec. 31, 2018 USD ($) segment	Dec. 31, 2017 USD ($)
Marketable Securities
Other-than-temporary impairment losses		$ 0
Realized gains or losses on the sale of securities		0	$ 0
Impairment of Long-Lived Assets
Impairment charges		$ 0
Number of operating segments \| segment		1
Number of geographic segments \| segment		1
Stock-Based Compensation
Expected dividend yield (as a percent)		0.00%
3.00% Convertible notes \| Convertible debt
Stock-Based Compensation
Debt instrument stated rate	3.00%	3.00%
Debt instrument remaining discount amortization period	7 years	7 years