The couple separated earlier this year, and documents filed on 27 November finalised their divorce.
Diane, 48, who had legally changed her name to Diane Lane Brolin, has restored her name to Diane Lane.
According to the paperwork, the couple have a private financial agreement, and Diane is not seeking spousal support.
The actors were married in 2004, in a ceremony held at Josh's central California ranch.
Although Josh, 45, was said to be coping well with the split, he checked himself into rehab last month to deal with issues related to his drinking.
The Gangster Squad star said that he was "completely done" with alcohol after becoming embroiled in two altercations in one weekend.
Asked if the incidents would spur him to curb his drinking, he replied, "Absolutely. It won't be happening again. That's it. Completely done."
Josh is being treated at a facility in Northern California. "He realised he needed help and is committed to his sobriety," a source said.