What is intent id

Rasa Open Source
1 
"intent_ranking": [

        {

            "id": -524330963132238278,

            "name": "search",

            "confidence": 0.9998310208

        },

        {

            "id": 8101248223092409786,

            "name": "goodbye",

            "confidence": 0.0001617737

        },

        {

            "id": 4910286396229353105,

            "name": "greet",

            "confidence": 0.0000072255

        }

what are this ids for every intent