Where's my check?

My father was born in Alaska before it became a state, but moved to St. Paul when he was a child. So he missed out on the financial windfall going out to current Alaska residents. Why do residents of Alaska get oil profit rebate checks from the state government? Is the oil a state or national resource?

I guess the money comes from state taxes on oil company profits. But if the state has so much extra cash, why are they getting any federal subsidies at all? Among the states, Alaska is always one of the largest per-capita recipients of federal subsidies. Shouldn't they be able to pay their own way with all of the oil tax dollars they are receiving? Maybe this will change if they elect a new Senator and Representative in Congress this fall.