| Fair value of investment in certain entities that calculate net asset value per share. Includes, but is not limited to, by unit, membership interest, or other ownership interest. Investment includes, but is not limited to, investment in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. Excludes measurement of net asset value as estimate of fair value. | en-US | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |
| Alternative Investment, Fair Value Disclosure (Deprecated 2018-01-31) | en-US | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Alternative Investment, Fair Value Disclosure, Beginning Balance (Deprecated 2018-01-31) | en-US | http://www.xbrl.org/2003/role/periodStartLabel | http://www.xbrl.org/2003/role/link |
| Alternative Investment, Fair Value Disclosure, Ending Balance (Deprecated 2018-01-31) | en-US | http://www.xbrl.org/2003/role/periodEndLabel | http://www.xbrl.org/2003/role/link |
Index