Profit Sharing Payable - Summary of Profit Sharing From Private Equity, Credit, and Real Estate Funds (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Profit Sharing Payable Summary [Line Items]
Profit sharing payable	$ 894,082	$ 992,240
Private Equity Funds
Profit Sharing Payable Summary [Line Items]
Profit sharing payable	640,581	751,192
Credit
Profit Sharing Payable Summary [Line Items]
Profit sharing payable	247,521	234,504
Real Estate
Profit Sharing Payable Summary [Line Items]
Profit sharing payable	$ 5,980	$ 6,544