| 鉄軌道事業固定資産 | ja | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| 鉄軌道事業固定資産、鉄道事業 | ja | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| 鉄軌道事業固定資産合計 | ja | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |
| Non-current assets - railway (including tramway) | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Non-current assets - railway (including tramway) - RWY | en | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| Total non-current assets - railway (including tramway) | en | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |