| 鉄道・運輸機構未払金の返済による支出 | ja | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| 鉄道・運輸機構未払金の返済による支出、財務活動によるキャッシュ・フロー、鉄道事業 | ja | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| Repayments of accounts payable to Japan railway construction, transport and technology agency | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Repayments of accounts payable to Japan railway construction, transport and technology agency - FinCF - RWY | en | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |