Analytics event shows no values on firebase console

[edencakir]

I'm using firestack to log analytics event with the code below:

this.firestack.analytics.logEventWithName('showDetail', {
      'value': rowData.title,
      'title': rowData.title
    })
    .then(res => console.tron.display({name: 'Sent event named showDetail', value: res}))
    .catch(err => console.tron.display({name: 'You should never end up here', value: err}));

Firebase console does show the event and its name (showDetail in my case), value column is just -. Any ideas?