Restructuring Charges - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) Employees
Restructuring Cost and Reserve [Line Items]
Current peak workforce | Employees	34
Reduction in force, description	Due to the CUPID 2 results and following analysis of the CUPID 2 data, Celladon's board of directors approved a reduction of Celladon's peak workforce of 34 employees.
Employee severance and benefit arrangements	$ 4,000
Number of employees impacted | Employees	30
Retention payment accruals	$ 2,500
Facility lease termination costs	$ 1,127
Restructuring accruals description	Celladon recorded the additional accruals as restructuring charges in the consolidated statements of operations. The accrued restructuring balance as of December 31, 2015, is presented as a current liability in the consolidated balance sheets and was paid within the first quarter of 2016.
Asset impairment, net	$ 192
MYDICAR [Member]
Restructuring Cost and Reserve [Line Items]
Asset impairment, net	$ 200