It is rare we ever get exact numbers about a game's entire budget, especially in any official capacity. Companies much prefer letting people guess and spread rumours than actually defining their financials.
CD Projekt RED have proven time and time again that they are a different kind of company though. In, fact in a recent investors call they outlined it specifically. According to GameSpot, the game including marketing costs came to a total of $81 million. For a game this size, including the marketing on top, that seems very low indeed. For comparison, it is believed that Grand Theft Auto V cost around $265 Million. There was even that rumour floating around that Destiny cost $500 million (even though the validity of that is uncertain.). So yeah, peanuts comparatively.
Take a look at the breakdown by the developer here:
It's nice to see a company being open about their budget. I'd love to see this kind of break down more often. It helps inform the market and makes comparison much easier. Granted, that is probably exactly why it doesn't happen so much.