The deal will be signed once the Cowboys free enough salary cap space, Schefter reports.
Durant, 28, had perhaps his best year as a pro last season but seemed to be the odd man out in Detroit. The team re-signed several of its free agents, but, despite being second on the team with 103 tackles, Durant wasn't given a new contract.
Lions general manager Martin Mayhew indicated recently that the team was looking to go in a different direction.
"I really don't know how it's going to play out," Mayhew said recently. "I know we've got some young guys we drafted at that position. We kind of want to see those guys. I would never say never."