| Interest, dividends and other income | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Interest, dividends and other income-OI-INS | en | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| Interest, dividends and other income | en | http://disclosure.edinet-fsa.go.jp/jppfs/ins/role/label | http://www.xbrl.org/2003/role/link |
| 利息及び配当金等収入 | ja | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| 利息及び配当金等収入、経常収益、保険業 | ja | http://www.xbrl.org/2003/role/verboseLabel | http://www.xbrl.org/2003/role/link |
| (うち利息及び配当金等収入) | ja | http://disclosure.edinet-fsa.go.jp/jppfs/ins/role/label | http://www.xbrl.org/2003/role/link |