Parameter in anonymous function?

Question

Apache Cordova

window.plugins.OneSignal.getIds(function(ids) {
        document.getElementById("OneSignalUserId").innerHTML = "UserId: " + ids.userId;
        document.getElementById("OneSignalPushToken").innerHTML = "PushToken: " + ids.pushToken;
        console.log('getIds: ' + JSON.stringify(ids));
        alert("userId = " + ids.userId + "\npushToken = " + ids.pushToken);
    });

I can’t understand where this ids comes from and how to access it from outside.