I found this write-up about the Dogme 95 movement and how Lars von Trier made The Idiots really interesting. This article covers the Dogme 95 films and the movement that created them.

From Wikipedia:

The goal of the Dogme collective is to purify filmmaking by refusing expensive and spectacular special effects, post-production modifications and other technical gimmicks. The filmmakers concentrate on the story and the actors’ performances.

They believe this approach may better engage the audience, as they are not alienated or distracted by overproduction. To this end, Lars von Trier and Thomas Vinterberg produced ten rules to which any dogme film must conform. These rules, referred to as the “Vow of Chastity,” are as follows:

1. Filming must be done on location. Props and sets must not be brought in. If a particular prop is necessary for the story, a location must be chosen where this prop is to be found.

2. The sound must never be produced apart from the images or vice versa. Music must not be used unless it occurs within the scene being filmed, i.e., diegetic.

3. The camera must be a hand-held camera. Any movement or immobility attainable in the hand is permitted. The film must not take place where the camera is standing; filming must take place where the action takes place.

4. The film must be in colour. Special lighting is not acceptable (if there is too little light for exposure the scene must be cut or a single lamp be attached to the camera).

5. Optical work and filters are forbidden.

6. The film must not contain superficial action (murders, weapons, etc. must not occur.)

7. Temporal and geographical alienation are forbidden (that is to say that the film takes place here and now).

8. Genre movies are not acceptable.

9. The film format must be Academy 35 mm.

10. The director must not be credited.

   

I hope this was informative.