| 特定債務者支援引当金の増減(△) | ja | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| 特定債務者支援引当金の増減(△)、営業活動によるキャッシュ・フロー、銀行業 | ja | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| Increase (decrease) in provision for possible loss on support of specific borrowers | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Increase (decrease) in provision for possible loss on support of specific borrowers-OpeCF-BNK | en | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |