| 債券貸借取引支払利息 | ja | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| 債券貸借取引支払利息、経常費用、銀行業 | ja | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| (うち債券貸借取引支払利息) | ja | http://disclosure.edinet-fsa.go.jp/jppfs/bnk/role/label | http://www.xbrl.org/2003/role/link |
| Interest expenses on cash collateral received for securities lent | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Interest expenses on cash collateral received for securities lent - OE - BNK | en | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| Interest expenses on cash collateral received for securities lent | en | http://disclosure.edinet-fsa.go.jp/jppfs/bnk/role/label | http://www.xbrl.org/2003/role/link |