Genius or Accidental Value Bet?

In limit poker, I'm fairly sure the correct move on the river is to check and call. In no-limit, I'm not exactly sure. I can't explain why I bet 300 chips, because it feels like a bet that will only get called when beaten. But at the moment, for some reason I felt like that was a fair value bet. Consider the way he called all those bets throughout the hand.

I don't know. Either it's genius or I was lucky to find someone dumb enough to call that bet.

Anyway the deck is hitting me in the face right now. I can't seem to lose a hand and I'm knocking people out left right and centre.

Party Poker No-Limit Hold'em Tourney, Big Blind is t30 (7 handed) converter

Hero (t1510)
MP1 (t1840)
MP2 (t700)
CO (t1150)
Button (t1375)
SB (t740)
BB (t685)

Preflop: Hero is UTG with As, Ad.
Hero raises to t90, 2 folds, CO calls t90, 3 folds.

Flop: (t225) Jc, 7d, 6h (2 players)
Hero bets t90, CO raises to t180, Hero calls t90.

Turn: (t585) 4c (2 players)
Hero checks, CO bets t125, Hero raises to t250, CO calls t125.

River: (t1085) Jd (2 players)
Hero bets t300, CO calls t300.

Final Pot: t1685

Results below:
Hero has As Ad (two pair, aces and jacks).
CO has Qh Ah (one pair, jacks).
Outcome: Hero wins t1685.