Canna are closely related to 'Bird of Paradise' or Strelitzia. To a degree they even share similarities in appearance with Strelitzia. Heliconia and Banana Plants are also related in this same family of plants. However, Canna have been highly cultivated and as a result are easier to germinate from seed and grow, especially in cooler temperature zones.

I have had very good success dividing the rhizomes of Strelitzia Reginae and spreading them around. They are very resilient. I expect that you will likely have similar success with Canna, but sorry, I have yet to have fully grown Canna to work with so am not a certain source of info on that. Strelitzia Nikolai, the Giant Bird of Paradise, seems to have a different structure of rhizomes and appears more difficult to divide or separate. I broke into one of mine to see if I could and was discouraged by what I found. So in conclusion, even within the same genus, division may be disimilar and either easy or difficult.

The only way to find out is to try it. Search the web for 'Canna Propogation' first and see if you can find any write-ups on division of the tubers to guide you first.

Good Luck!