Fair Value Measurements - Investments in Company-Sponsored Funds (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2015 USD ($)	Sep. 30, 2015 USD ($)
Investment Holdings [Line Items]
Fair Value	$ 7,966	$ 7,966
Unfunded Commitments	1,251	1,251
Hedge Funds [Member]
Investment Holdings [Line Items]
Fair Value	2,304	$ 2,304
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	5,662	$ 5,662
Unfunded Commitments	$ 1,251	$ 1,251
Investments Lock In Period	10 years
Maximum [Member] | Hedge Funds [Member]
Investment Holdings [Line Items]
Investments Lock In Period	1 year