| Surplus | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Surplus-INV | en | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| Total surplus | en | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |
| Total surplus | en | http://disclosure.edinet-fsa.go.jp/jppfs/NonConsolidatedInterim/role/totalLabel | http://www.xbrl.org/2003/role/link |
| 剰余金 | ja | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| 剰余金、投資業 | ja | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| 剰余金合計 | ja | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |
| 剰余金合計 | ja | http://disclosure.edinet-fsa.go.jp/jppfs/NonConsolidatedInterim/role/totalLabel | http://www.xbrl.org/2003/role/link |