Do we pay taxes on the $10k we received from an inheirited IRA (parent) which was more than 5 years old and if so where do we put that in the tax forms?

Both my wife's parents died in 2017. We have filed their tax forms, but we received about $10k from her dad's IRA as a lump sum distribution (her sister also got $10k). How do I report that? And do I need to report it? I've gotten different answers from different people...