Thanks OP. I had no idea about this until reading your post.
FYI, I am cutting and pasting an excerpt from the Alberta Motor Association (CAA) website with respect to this (hope this is within the rules). The full webpage is at:
http://www.ama.ab.ca/travel/international-driving-permit-
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What else you need to know...
The IDP must be issued at a CAA office in Canada and cannot be obtained or renewed elsewhere. Once issued, the IDP is valid for one year from the date of issue, providing your Canadian licence is valid for the duration of your trip. Your valid Canadian provincial driver's licence must accompany the IDP at all times. An IDP cannot be post-dated, extended or renewed and a new application form must be completed each time a new IDP is required. Traceable methods for delivery are recommended. An additional fee will be applied for registered mail and courier service.
Effective January 1, 2013, travellers that wish to drive in Florida without obtaining a Florida driver license will be required to have an International Driving Permit to accompany their out of country license. This applies to any vehicle, including rental vehicles. The International Driving Permit must be in the customer’s name and from their country of residence.
Why did the law change?
The purpose of the permit is for the English translation. Obviously, a license issued in Canada and other English speaking countries is already written in English so the permit is admittedly a little redundant but that is technically the law at this point.
What will happen to a driver who drives without an IDP?
Without an IDP, a driver is therefore driving without a valid license and if stopped, law enforcement has the option of 1/ arresting the driver and taking him/her to jail 2/ giving the driver a citation with a mandatory court appearance.