| Decrease through balances reversed in current period, regulatory deferral account credit balances | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Decrease through balances reversed in current period, regulatory deferral account credit balances | en | http://www.xbrl.org/2009/role/negatedLabel | http://www.xbrl.org/2003/role/link |
| The decrease in regulatory deferral account credit balances resulting from balances reversed in the current period. [Refer: Regulatory deferral account credit balances] | en | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |
| Laghdú trí iarmhéideanna a aisiompaítear le linn na tréimhse reatha, iarmhéideanna sochair cuntais iarchurtha rialála | ga | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| An laghdú ar iarmhéideanna dochair cuntais iarchurtha rialála a leanann as iarmhéideanna arna n‑aisiompú sa tréimhse reatha. [Féach: Iarmhéideanna sochair cuntais iarchurtha rialála] | ga | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |
| Laghdú trí iarmhéideanna a aisiompaítear le linn na tréimhse reatha, iarmhéideanna sochair cuntais iarchurtha rialála | ga | http://www.xbrl.org/2009/role/negatedLabel | http://www.xbrl.org/2003/role/link |