Instant Cash tokens give you a few hours, or days worth of Cash right away depending on the token used! For example a 4 hour token will instantly give you 4 hours' worth of Cash, and a 3 day token will give you 3 days of Cash as well.

The amount of Cash given is dependent on the Idle Cash generation of that entire continent at that moment. So if you use an Instant Cash token on the Coal Mine and you also have your Gold Mine, Ruby, Diamond, and Emerald unlocked you'll gain the Cash generated from all of those mines as well! However, any mines that are still to be opened will not be counted towards the Cash given! So be sure to open as many mines as you can before you use one! :)

Please also note if you purchase an Instant Cash Token with Super Cash in the shop it will use the Instant Cash Token right away for the continent you're currently in.