| 有価証券利息配当金 | ja | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| 有価証券利息配当金、経常収益、銀行業 | ja | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| (うち有価証券利息配当金) | ja | http://disclosure.edinet-fsa.go.jp/jppfs/bnk/role/label | http://www.xbrl.org/2003/role/link |
| Interest and dividends on securities | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Interest and dividends on securities-OI-BNK | en | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| Interest and dividends on securities | en | http://disclosure.edinet-fsa.go.jp/jppfs/bnk/role/label | http://www.xbrl.org/2003/role/link |