Consolidated Balance Sheet Details - Other Assets (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt acquisition costs	$ 241	$ 969
Deposits	1,033us-gaap_DepositsAssetsNoncurrent	431us-gaap_DepositsAssetsNoncurrent
Restricted cash	0	200
Other assets	99zgnx_OtherAssetsOtherNoncurrent	125zgnx_OtherAssetsOtherNoncurrent
Total other assets	5,505us-gaap_OtherAssetsNoncurrent	6,614us-gaap_OtherAssetsNoncurrent
Aradigm [Member]
Prepaid royalty expense	2,286	2,571
Alkermes [Member]
Prepaid royalty expense	$ 1,846	$ 2,318

Net amount of long-term deferred finance costs capitalized at the end of the reporting period.

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

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