| 有形及び無形固定資産 | ja | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| 有形及び無形固定資産、電気事業 | ja | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| 有形及び無形固定資産合計 | ja | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |
| Plant and equipment, and intangible assets | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Plant and equipment, and intangible assets-ELE | en | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| Total plant and equipment, and intangible assets | en | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |