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Fair Value Measurements - Investments in Company-Sponsored Funds (Details) $ in Thousands | 3 Months Ended
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Mar. 31, 2016 USD ($)
Investment Holdings [Line Items] |
Fair Value | $ 7,262
Unfunded Commitments | 1,251
Hedge Funds [Member] |
Investment Holdings [Line Items] |
Fair Value | 2,396
Unfunded Commitments | $ 0
Redemption Frequency | Quarterly - Annually
Investment Redemption Notice Period Minimum | 30 days
Investment Redemption Notice Period Maximum | 120 days
Private Equity Funds [Member] |
Investment Holdings [Line Items] |
Fair Value | $ 4,866
Unfunded Commitments | $ 1,251
Investments Lock In Period | 10 years
Maximum [Member] | Hedge Funds [Member] |
Investment Holdings [Line Items] |
Investments Lock In Period | 1 year

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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 + Details
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