That's moving out of state, not going on vacation.
Each custody order reads differently.
Some don't permit ANY travel beyond a certain radius of the county seat, the sate, etc...; and some have no limitations at all.
Some simply require notice of the travel, and require contact information during the time the child is away.
Each person should read his or her custody order, or consult a licensed attorney in her or his state to remain in compliance at all times.
That said, many people don't care, because they like to jerk chains, ring bells, and push buttons.
I'd hate to tell a judge that some unknown dude (or dudette) told me I could take sweet Sally to Timbuktu, or Tallahassee.
In some cases, the other parent doesn't care, and many parents worry about giving gentle George a baby aspirin.
Actually one parent can't deny the other parent from taking Princess to Disneyworld.
However, that same parent can scream, shout, howl, yell, and squeal like a banshee when the parent and the child return, eventually telling it to the judge.
You takes yer chances, you gets what you gets!
YMMV, proceed with caution, or damn the torpedoes, full speed ahead!