The movie is hilarious but almost all the humor is adult. The violence is all done in a humerous fashion. The sexual content is a little on the heavy side (including mentioning a possible threesome, cheating on a spouse, and a foot fetish, in different scenes), but is also done humorously and not raunchy or overly graphic. The partial nudity is a man's rear end and not part of any sex scene.
The movie is great for adults and older teens. The end of the movie is uplifting because of the repairs made in the relationship between a divorced father and his 17 year old son. My daughter is a naive 15, and we still won't let her watch it but probably will when she is 16. It is one of my favorite movies, and I agree that it is a borderline R movie.