Was that a speech impediment or an accent?

The way the Colonel (Tom Hanks) speaks in this movie. Is that supposed to be some sort of regional or foreign accent? Or is that supposed to be speech impediment?

It was incredibly distracting for me. My wife and I had recently watched an episode of Criminal Minds where a mentally impaired man was torturing and murdering young girls. The character in that show spoke much like the Colonel in this movie, with the intent of making him sound retarded.

Obviously, with his success and business savvy, the Colonel was not retarded, so what was the intent? When people pronounce the letter R as a W sound, I consider that an impediment.