Loans Receivable and Other Lending Investments, net (Reserve for Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Allowance for Loan Losses [Roll Forward]
Reserve for loan losses at beginning of period	$ 79,389	$ 109,671	$ 85,545	$ 108,165
(Recovery of) provision for loan losses	(600)		(5,528)
(Recovery of) provision for loan losses	(600)	700	(5,528)	2,206
Charge-offs	0	0	(1,228)	0
Reserve for loan losses at end of period	$ 78,789	$ 110,371	$ 78,789	$ 110,371