If something was a long time ago, just summarize it and keep it short and sweet. Nobody needs to read 8 bullet points on an internship you had 7 gigs ago which has no relevance to the job you're applying for. Contractors are particularly bad offenders here in my experience. No hiring manager will read through a 13 page resume for somebody with 6 years experience. As the TFA mentions, use that valuable space to highlight more recent, relevant experience and put your best foot forward. Everything else is just noise.