AK, feeling a bit pasive...

[Ace-Ex]

I bet the river. Figure 20% he was on a draw that missed and is flat out bluffing because of the A. 50% chance he has a weaker Ace. 30% chance he's being sneaky with a Q, but I rarely see that sort of play. If Button had called you likely would have been beaten, though. Chances are if he had a Q he would have re-raised. You still would need to call any re-raise though since your hand is pretty strong.