Laravel delete related records

Question

I've got 1 company. That company hasMany departments. When I want to softdelete company the departments should be softdeleted aswell. Right now I'm doing that like this:

Company.php

protected static function boot()                         
{                                                        
    parent::boot();                                      
    static::deleting(function($company) {                
        foreach($company->department as $department)     
        {                                                
            $department->delete();                       
        }                                                
    });                                                  
}   

But for some reason only the first department is beeing softdeleted while the company has for example 17 departments.

What am I doing wrong??? I'm looking for hours right now still no solution!

--EDIT--

A department hasMany Employees.

protected static function boot()
    {
        parent::boot();
        static::deleting(function($department) {
            Employee::where('DepartmentId','=',$department->DepartmentId)->delete();
        });
    }       

Answer 1

Try this:

$departmentID[] = Department::where('company_id', '=', $company->id)->select('id')->distinct()->get()->toArray();
Department::where('company_id', '=', $company->id)->delete();

DB::table('users')->whereIn('department_id', $departmentID)->delete();

See, if that helps.