Combobox selected text not getting saved

I want to save the selected value from the combobox that is the text inside the combobox in database.
but the Id is getting saved in database.

The table name is Company with two colummns com_id and com_name in Database

   

created a domaincontext also domain service ...... using RIA Services

//to load the Company

      DictionaryDomainContext orgdemo = new DictionaryDomainContext();
            LoadOperation dict = orgdemo.Load(orgdemo.GetCompaniesQuery());
            CmbOrg.ItemsSource = dict.Entities;


//the value code which is getting saved to Database
 dc.Org_Name = CmbOrg.SelectedValue.ToString();