| 営業収益 | ja | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| 営業収益、電気通信事業営業損益 | ja | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| 営業収益合計 | ja | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |
| Operating revenue | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Operating revenue-OIL-telecommunications | en | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| Total operation revenue | en | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |