NEW YORK (AP) -- Jonathan Martin, the former NFL tackle who abruptly left the Miami Dolphins and has since said he attempted suicide, is working on a memoir.

Atria Books editor Todd Hunter told The Associated Press on Thursday that the publisher has agreed to terms with Martin for "The Courage To Walk Away," co-written by Hilary Beard. Hunter says the book is tentatively scheduled for spring 2017.

Hunter's agent, Steve Ross, told the AP that the deal is worth six figures.

Martin made headlines when he walked out during the 2013 season amid reports he was bullied by teammates. He played for the San Francisco 49ers last year, but retired this summer, citing a back injury.

He posted on Facebook on Wednesday that he had tried to kill himself "on multiple occasions."