Reformatting a column to proper phone number

  Good morning!  I frequently download .csv files from Veterans of Foreign Wars of the United States that then need to have several columns reformatted for my in-house use.

  I'm having a devil of a time finding the source of information on how to convert a column that has this data format "(nnn) nnnnnnn" to the format I want as "nnn-nnn-nnnn".