Organization and Summary of Significant Accounting Policies - Additional Information (Detail)			12 Months Ended
	Mar. 22, 2016 shares	Jun. 06, 2013	Dec. 31, 2015 USD ($) Segment	Dec. 31, 2014 USD ($)
Significant Accounting Policies [Line Items]
Reverse stock split, description			Celladon effected a 1-for-15 reverse stock split on its issued and outstanding common stock
Agreement entered date			Nov. 18, 2015
Number of operating segments | Segment			1
Impairment charges on investment securities			$ 0
Investment securities, unrealized loss position for more than 12 months				$ 0
Short-term investments			$ 0	$ 70,513,000
Income tax benefit, likelihood of realized upon ultimate settlement			More than 50%
Subsequent Event [Member]
Significant Accounting Policies [Line Items]
Reverse stock split ratio	0.0666
Celladon Europe [Member]
Significant Accounting Policies [Line Items]
Ownership interest, percentage		90.00%
Reverse Merger [Member]
Significant Accounting Policies [Line Items]
Date of acquisition			Mar. 22, 2016
Reverse Merger [Member] | Subsequent Event [Member]
Significant Accounting Policies [Line Items]
Common stock outstanding share conversion ratio	0.0875219
Issuance of common stock in connection with acquisition | shares	0
Maximum [Member]
Significant Accounting Policies [Line Items]
Highly liquid investments original maturity period			3 months
Property and equipment estimated useful lives of the assets			5 years
Minimum [Member]
Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives of the assets			3 years