Folding A_K PF shorthanded. Mistake?

[Zetack]

I can't remember some of the details, sorry.

Home tourney, 19 players with rebuys. Down to 4 players. Payoffs 600, 485, 220, 100.

I'm the chip leader with about 21k, another guy is close to me in chips. I don't remember where the blinds were in this hand.

Blinds 500/1000. Min raise, then the guy to my right goes all-in for about 12K. My read on him isn't great, but he's loose and, particularly post flop, capable of putting in a lot of chips with marginal hands. I don't recall him pushing PF on any other hands up to that point.

Min raise guy is decently solid for a home game player, probably not aggressive enough, but hadn't done anything notably unusual.

I look down at A-Ko and fold.

This may be my first PF fold with A-K in a tourney, and I'm wondering if it was a mistake.

Based on this info, what do y'all think?

-Zetack