A judge has reduced the prison terms for a father and son who built Adelphia Communications into a cable television powerhouse before they were convicted of ruining it by using it as a piggy bank to pay for luxuries including a jet and 100 pairs of slippers.

The 15-year sentence of 82-year-old Adelphia founder John Rigas was reduced to 12 years and the 20-year sentence of his son Timothy Rigas was reduced to 17 years by U.S. District Judge Leonard B. Sand in Manhattan. The Rigases, convicted of charges including conspiracy, bank fraud and securities fraud, began serving their sentences last August.