| 金銭の信託運用損 | ja | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| 金銭の信託運用損、経常費用、銀行業 | ja | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| (うち金銭の信託運用損) | ja | http://disclosure.edinet-fsa.go.jp/jppfs/bnk/role/label | http://www.xbrl.org/2003/role/link |
| Loss on money held in trust | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Loss on money held in trust-OE-BNK | en | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| Loss on money held in trust | en | http://disclosure.edinet-fsa.go.jp/jppfs/bnk/role/label | http://www.xbrl.org/2003/role/link |