Legendary NFL head coach Dan Reeves, who spent 38 years in the league, has died. He was 77.

A statement from Reeves’ family was released on New Year’s Day through the Atlanta Falcons organization. The statement said that Reeves died from complications with dementia and that he died “peacefully and surrounded by his loving family at his home in Atlanta.”

Reeves coaches for 4 NFL organizations during his career. He started with the Dallas Cowboys, where he was an assistant coach in 1972, then from 1974-80.

The first head coaching job for Reeves came in 1981, when he took over the Denver Broncos. He led the organization through 1992. He also coached the New York Giants (1993-96) and Atlanta Falcons (1997-2003).

Reeves won a Super Bowl as a player and an assistant coach with the Cowboys. He also led the Broncos and Falcons to Super Bowl appearances. His career record as an NFL head coach was 201-174-2.