Optimal DB Schema

The only thing I'd probably do differently is have the issue_id foreign key on the issue_details table so that you could have a one to one relationship.

So if you were using Eloquent you could do something like this.

echo $issue->details->name;

I'm not entirely sure what you'll be storing in the details table though, perhaps there will be multiple details for an issue in which case you'd have a many to many relationship.