The music was written by Bernie Miller, with lyrics added later by Jerry Leiber and Mike Stoller.
[1] It was popularised with a recording by the quartet of the American saxophonist and composer Gerry Mulligan, on the 1952 album of the same name, which also featured Chet Baker on trumpet.
The tune was a popular choice for musicians jamming at the time, though information about the composer ("Bernie" Miller) himself is scarce, all that people really know of him is that he was a piano player from Washington DC.
Later on in Mulligan's life, he took the same changes but invented a new melody to fit over the piece, entitling it 'Idle Gossip'.
[2] The melody of the A section is primarily chromatic and conjunct, except the quaver length four note arpeggios at the end of each second bar.