It pegs on the + side. And when I go to idle under these conditions, the gauge does come down. If I remember right, it doesn't make it back to the center, it's still on the + side, but not pegged at idle.
Forgot to ask did you recently change anything? Like the alternator? or wiring? or the VR?
Pull the connector off at the VR and see if it goes to center or some left. This will tell you that you don't have a problem in the harness or inside the alternator (shorted brush)