Commitments and Contingencies - Capital Commitments (Details) $ in Millions	Dec. 31, 2015 USD ($)
Loss Contingencies [Line Items]
Unfunded commitment	$ 2,870.6
Corporate Private Equity
Loss Contingencies [Line Items]
Unfunded commitment	1,790.9
Global Market Strategies
Loss Contingencies [Line Items]
Unfunded commitment	335.3
Real Assets
Loss Contingencies [Line Items]
Unfunded commitment	709.7
Investment Solutions
Loss Contingencies [Line Items]
Unfunded commitment	$ 34.7