Is there a method to completely remove personal details (such as telephone numbers and email addresses) from a post? They are often put in by new users who aren't familiar with the site (or the risks of posting such information). While these details can be edited out of the body of the post, they will remain in the edit history and, therefore, remain viewable.
If it's a legitimate post that someone has accidentally included personal info in, and not spam, then you can flag the post for moderator attention and ask them to redact the revision history.
Moderators can, with a bit of effort, redact parts of the revision history to remove sensitive information.
See also main meta at What should I do if a user posts sensitive information as part of a question or answer?:
Often, simply editing is enough... But in cases where someone could suffer serious consequences if the information remains visible on the 'Net (keys that can't be changed, 3rd-party medical information, etc.), you'll want to make sure it's thoroughly purged. Moderators can redact individual revisions to remove all traces of such information from both the post and its history; flagging will alert them to the nature of the problem.