| Available-for-sale Securities, Gross Realized Gain (Loss) | en-US | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Available-for-sale Securities, Gross Realized Gain (Loss), Total | en-US | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |
| This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities. | en-US | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |