After you log on locally to the machine and pull it out of the domain, the laptop will know it doesn't belong anymore.
The active directory will still have a computer account with that name within an OU. Find the computer name within your AD and delete it. You can do that by using Active directory users and computers. Then open Active directory sites and services and find each domain controller within your AD. These would be listed under sites then site name (ie headquarters, remote location), expand the servers container and expand the domain controller by name. Highlight the ntds settings you will see one or two entries in the right hand pane. Right click the entry and replicate now. I would suggest doing this from each DC in each site. Some may argue that is overkill but I don't have issues when I go that far with it.
If you need further assistance let me know.