couchbase server not return id within record using c# code

when we get records from couchbase server using select query not get id of each record

my code below . what i am missing

var clientConfiguration = new ClientConfiguration();
clientConfiguration.Servers = new List { new Uri("http://localhost:8091/pools/") };

List objDocList = new List();
Cluster Cluster = new Cluster(clientConfiguration);
var bucket = Cluster.OpenBucket();
var result = bucket.Query("select * from testbucket");


foreach (var row in result)
{

dynamic propJSON = JsonConvert.SerializeObject(row);

//propJSON not contain id

}

I want id for updating record