Background and Organization - Additional Information (Detail) $ / shares in Units, $ in Thousands			3 Months Ended		6 Months Ended
	Aug. 17, 2015 USD ($) $ / shares shares	Jul. 08, 2015 $ / shares shares	Jun. 30, 2016 USD ($) $ / shares shares	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) $ / shares shares	Jun. 30, 2015 USD ($)	Dec. 31, 2015 $ / shares shares	Jul. 21, 2015 $ / shares shares	Jul. 20, 2015 $ / shares shares	Jul. 07, 2015 $ / shares shares
Background And Organization [Line Items]
Description of the stock split arrangement					On July 8, 2015, ViewRay, Inc. (f/k/a Mirax Corp.), or ViewRay, we, us, our, or the Company, completed a 1.185763-for-1 forward stock split of its common stock in the form of a dividend with the result that 4,343,339 shares of common stock, par value $0.001 per share, outstanding immediately prior to the stock split became 5,150,176 shares of common stock, par value $0.001 per share, outstanding immediately thereafter.
Stock split conversion ratio		1.185763
Common stock, shares outstanding		5,150,176	38,362,134		38,362,134		38,204,960			4,343,339
Common stock, par value | $ / shares		$ 0.001	$ 0.01		$ 0.01		$ 0.01	$ 0.01	$ 0.001	$ 0.001
Common stock, shares authorized			300,000,000		300,000,000		300,000,000	300,000,000	75,000,000
Net loss from operations | $			$ (12,115)	$ (12,174)	$ (25,483)	$ (20,629)
Net cash used from operations | $					$ (20,570)	$ (20,286)
Private Placement
Background And Organization [Line Items]
Private placement, common shares	5,884,504
Purchase price of share common stock, per share | $ / shares	$ 5.00
Private placement, value | $	$ 26,300
Blank Check Preferred Stock
Background And Organization [Line Items]
Preferred stock, shares authorized								10,000,000
Preferred stock, par value | $ / shares								$ 0.01