Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit): (Details) - $ / shares		8 Months Ended	9 Months Ended	12 Months Ended
Jan. 24, 2018	Aug. 30, 2018	Sep. 24, 2018	Dec. 31, 2017
Dividend yield (%)	0.00%	0.00%	0.00%	0.00%
Expected volatility (%)	37.90%	37.30%	36.40%	36.90%
Risk free interest rate (%)	1.75%	2.15%	2.21%	1.74%
Strike price	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Probability of if-converted scenario (%)	90.00%	90.00%	90.00%	90.00%
Probability assumed liquidation scenario (%)	10.00%	10.00%	10.00%	10.00%
Expected term of Option (years)	10 months 24 days	3 months 29 days	3 months	1 year
Option's fair value per share	$ 0.30	$ 0.04	$ 0.04	$ 0.33
Series B Preferred Stock [Member]
Strike price	$ 1.10	$ 0.44	$ 0.38	$ 1.13

Share based compensation arrangement by share based payment award fair value assumptions expected term of option years.

No definition available.

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- Definition

Share based compensation arrangement by share based fair value assumptions probability assumed liquidation scenario rate.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share based fair value assumptions probability of if converted scenario.

+ References

No definition available.

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- Definition

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

+ References

No definition available.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iv)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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