The American Idol results show, continuing to feature performances by renowned musical artists who mentor the contestants each week, will expand from 30 minutes to one hour on the following dates: Wednesday, April 11 (9/8c); Wednesday, April 18 (9/8c); and Wednesday, May 2 (9/8c) on FOX. Tonight's mentor is music icon Gwen Stefani. Upcoming mentors include Tony Bennett, Jennifer Lopez, Martina McBride, Bon Jovi and Barry Gibb.