Billy Joel is opening up about a tough moment with longtime friend and tourmate Elton John. In the second part of the new two-part HBO Documentary, "Billy Joel: And So It Goes," the "New York State of Mind" singer shared how John's public comments that he needed rehab strained their friendship.

Billy Joel acknowledged “bad blood” between himself and Elton John in the second installment of his two-part HBO documentary “Billy Joel: And So It Goes,” released Friday. Joel explained the pair’s fallout occurred after John publicly insisted he needed to go to rehab.

Now, a two-part HBO documentary is exploring the life, career and personal struggles of Billy Joel, providing an expansive look at the man behind the music. Billy Joel’s former business manager and wife,

Billy Joel and Elton John haven’t always seen eye to eye. During the newly released second part of HBO’s “Billy Joel: And So It Goes” documentary, Joel revealed how John’s public push for him to enter rehab caused a major rift between the two music superstars.

Directed by Susan Lacy and Jessica Levin, Billy Joel: And So Goes is split into two parts, with Part 1 airing tonight on HBO and HBO Max, and Part 2 airing next week, on Friday July 25. The film features extensive present-day interviews with Joel himself (now 76, and recent diagnosed with a brain condition that forced him to cancel his tour).

So It Goes’ will fully prepare you to teach a college class on Joel the angry young man, Ex-Wife Guy, and unlikely superstar.

Billy Joel talks about his landmark Madison Square Garden residency in an exclusive clip for part 2 of the new HBO documentary 'Billy Joel: And So It Goes', which premieres on Friday, July 25.