Type of Action: Full Attack Action
A double move allows a creature to move up to twice its listed speed with one (or more) of its available movement types. A double-move is considered a single action, so there is no need for the creature to stop at the end of its first move action. The creature must obey all normal rules for passing through enemy creatures, threatened squares, blocked or obstructed squares, difficult terrain, etc.
Like walking, a double move is a cautious form of movement, though it still provokes attacks of opportunity if you leave any space that is threatened by one or more enemies. Note that, because it is a single action, you can only be the target of one attack of opportunity per enemy creature you provoke, even if you leave multiple spaces threatened by the same enemy.