| Debt Securities, Available-for-Sale, Gain (Loss) | en-US | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Debt Securities, Available-for-Sale, Gain (Loss), Total | en-US | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |
| Amount of unrealized and realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). | en-US | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |