I have a document that includes over 200 pages. I have been asked to locate any and all words or phrases in Parenthesis, remove the Parenthesis and replace the words with words in itallics. Please note that the words are of varying length and in some instances the issue includes complete phrases.

Is there a way to do this in Word 2013?

You can use the following wild card Find/Replace:
Find What:
\(([!\(\)]{1,})\)
Replace With:
\1
And do not forget to specify italic font format for the replacement in the Ctrl+H dialog.