| Cash and securities deposited in a special reserve account for the exclusive benefit of customers pursuant to regulations other than SEC Regulations and the Commodity Exchange Act. | en-US | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |
| Cash and Securities Segregated under Other Regulations (Deprecated 2019-01-31) | en-US | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Cash and Securities Segregated under Other Regulations, Total (Deprecated 2019-01-31) | en-US | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |