Idris, who had three years remaining on his contract with the Titans, had expressed a desire to return to Sydney to be closer to his family.
The Titans' decision to release Idris after two seasons in Queensland will mean Panthers' speedster Brad Tighe will head north to the Gold Coast on a two-year deal.
Idris said he'd struggled to live away from his family, particularly with his mother battling an illness.
"I've enjoyed my time here at the Titans and I'm grateful that the club has favourably considered my request for a release," he said.
"For personal reasons, I have decided it would be best to be closer to my family as my mum has been ill for the past year and it's been difficult living interstate.
"I wish the club all the best and am looking forward to the opportunity with the Panthers."
Titans chief executive Graham Annesley said the club couldn't stand in the way of the 23-year-old's desire to be closer to his family despite their disappointment at having to release the star.
"We are dealing with people's lives and at times, we have to put the best interests of people first," Annesley said.
"Jamal has a really close relationship with his family and we respect his desire to spend more time with them in Sydney."
Idris, who played one match for the Blues in the 2010 Origin series as well as a Test for Australia in 2011, struggled with injuries in his two years at the Titans.
He made just 35 appearances in two years with his 2013 campaign coming to a premature end after he broke his leg in a round 16 loss to Newcastle.
"Jamal showed everyone last season exactly what he is capable of, it was just unfortunate that injury struck right when he was playing some of his best football," Titans coach John Cartwright said.
"It's unfortunate that he is moving on but it's the best outcome for both Jamal and his family and we respect that."
Tighe, 29, has played 157 matches for the Panthers and Newcastle, and Cartwright said his arrival should ease the damage caused by Idris's departure.
"Brad is a real speedster who I'm sure many fans will remember from late in the 2012 season when he scored three tries against us," he said.
"It'll be exciting to see him in Titans colours next season."