Where did the former name of Kennedy Airport 'Idlewild' come from?

Construction on Idlewild International Airport (presently John F. Kennedy International Airport) began in 1942. The airport took its name from the Idlewild Golf Course that it replaced. Planning began during the administration of Mayor Fiorello H. LaGuardia (1882-1947, mayor 1934-45) and called for 1,000 acres of development. After six years of construction, the airport opened on July 1, 1948.