Debt - Schedule of Maturities of Long-term Debt (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Debt Disclosure [Abstract]
2015	$ 0
2016	6,667
2017	6,667
2018	6,666
2019	0
Thereafter	7,000
Principal balance outstanding	27,000zgnx_LongTermDebtIncludingInterest
Less unamortized discounts	(5,297)
Total long-term debt	21,703zgnx_LongtermDebtExcludingDiscounts
Less current portion	0
Long-term portion	$ 21,703

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

+ Details

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- Definition

Long-term Debt Excluding Discounts

+ References

No definition available.

+ Details

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- Definition

Long-term Debt Excluding Discounts, Current Maturities

+ References

No definition available.

+ Details

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- Definition

Long-term Debt Excluding Discounts, Excluding Current Maturities

+ References

No definition available.

+ Details

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- Definition

Long-term Debt, Including Interest

+ References

No definition available.

+ Details

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- Definition

Long-term Debt Including Interest, Maturities, Repayments of Principal in Next Twelve Months

+ References

No definition available.

+ Details

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- Definition

Long-term Debt Including Interest, Maturities, Repayments of Principal in Year Four

+ References

No definition available.

+ Details

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- Definition

Long-term Debt Including Interest, Maturities, Repayments of Principal in Year Three

+ References

No definition available.

+ Details

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- Definition

Long-term Debt Including Interest, Maturities, Repayments of Principal in Year Two

+ References

No definition available.

+ Details

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- Definition

Long-term Debt, Maturities Including Interest, Repayments of Principal in Year Five

+ References

No definition available.

+ Details

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- Definition

Long Term Debt, Maturities Including Interest, Repayments Of Principal Thereafter

+ References

No definition available.

+ Details

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