Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2018
At The Market Offering Program
Offering cost	$ 10,631	$ 10,637
Direct Registered Offering
Offering cost	$ 0	$ 177

Adjustments to additional paid in capital stock issued offering costs.

No definition available.

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Namespace Prefix:	vray_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration