On Sunday (September 16), Urban and Nicki Minaj were confirmed as the new judges on the Fox programme, joining Mariah Carey and Randy Jackson on the panel.
Urban said in a statement: "It's really an honour to have been invited to be a part of the American Idol family. I'm looking forward to working with everyone and to seeing the same passion that I have for music in all the participants."
The country star previously admitted that he would love to be a judge on Idol and always hoped it would happen.
Days later, Urban exited The Voice Australia after one season as a coach alongside Seal, Delta Goodrem and Joel Madden, fuelling more fire to the Idol rumours.
Season 12 of American Idol will kick off in January 2013.
Watch the music video for Keith Urban's 'Long Hot Summer' below: