| Net movement in regulatory deferral account balances related to profit or loss directly associated with discontinued operation | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| The amount of the net movement in regulatory deferral account balances related to profit or loss that are directly associated with a discontinued operation. [Refer: Net movement in regulatory deferral account balances related to profit or loss; Discontinued operations [member]] | en | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |
| Variazioni nette dei saldi dei regulatory deferral account relative a utili o perdite associate direttamente ad attività operative cessate | it | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| L'ammontare delle variazioni nette dei saldi dei regulatory deferral account relative a utili o perdite che sono associate direttamente ad attività operative cessate. [Rif: Variazioni nette dei saldi dei regulatory deferral account relative a utili o perdite; Attività operative cessate [member]] | it | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |