Real Estate Fund Investments - Summary of the Fair Value of Property Funds and the Alternative Investment Fund Consolidated with Balance Sheet and Income from Fund Investments (Parenthetical) (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015
Investment Holdings [Line Items]
Asset management fee income		$ 7,754
Noncontrolling Interest [Member]
Investment Holdings [Line Items]
Asset management fee income	$ 521		$ 5,481