Development Award and Deferred Revenue (Tables)
|12 Months Ended|
Dec. 31, 2017
|Deferred Revenue Disclosure [Abstract]|
|Schedule of Deferred Revenue||
Deferred revenue consisted of the following:
Tabular disclosure of the type of arrangements and the corresponding amounts that comprise the current and noncurrent balance of deferred revenue as of the balance sheet date.
Reference 1: http://www.xbrl.org/2003/role/presentationRef