Warrants - Issued November 4, 2014 Black Scholes (Details) - $ / shares	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Fair value assumptions and methodology for assets and liabilities
Number of warrants (in shares)	563,998	913,441
Warrants Issued November 4, 2014, Liability
Fair value assumptions and methodology for assets and liabilities
Number of warrants (in shares)	77,677	77,677
CDTi stock price (in dollars per share)	$ 1.65	$ 4.70
Strike price (in dollars per share)	$ 8.50	$ 8.50
Expected volatility	95.00%	96.60%
Risk-free interest rate	0.90%	1.60%
Expected life in years	3 years 10 months 24 days	4 years 4 months 24 days