Organization and Significant Accounting Policies, Stock-Based Compensation Expense (Details)	12 Months Ended
Dec. 31, 2017
RSUs [Member]
Stock-Based Compensation [Abstract]
Vesting period	4 years
2015 Equity Incentive Plan [Member] \| Employee Stock Options [Member]
Stock-Based Compensation [Abstract]
Vesting period	4 years
Award term	10 years
2015 Equity Incentive Plan [Member] \| Employee Stock Options [Member] \| One Year from Date of Grant [Member]
Stock-Based Compensation [Abstract]
Vesting percentage	25.00%
2015 Equity Incentive Plan [Member] \| Board of Director Stock Options [Member]
Stock-Based Compensation [Abstract]
Vesting period	4 years
Award term	10 years

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- Definition

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.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

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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.

+ 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 (a)(2)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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