Keith Ian Carradine ( KARR-ə-deen; born August 8, 1949) is an American actor who has had success on stage, film, and television. He is known for his roles as Tom Frank in Robert Altman's film Nashville, Wild Bill Hickok in the HBO series Deadwood, FBI agent Frank Lundy in Dexter, Lou Solverson in the first season of Fargo, and US president Conrad Dalton in Madam Secretary. He also had a recurring role as Penny's father Wyatt in the CBS sitcom The Big Bang Theory. As a member of the Carradine family, he is part of Carradine family of actors that began with his father, John Carradine.

Source: Wikipedia (https://en.wikipedia.org/wiki/Keith_Carradine)