Real Estate Loans Receivable (Details 1) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Summary of allowance for losses on loans receivable
Balance at beginning of year		$ 0	$ 0	$ 0
Provision for loan losses	[1]	6,935	0	0
Charge-offs		(372)	0	0
Balance at end of year		6,563	0	0
Summary of loan impairments
Balance of impaired loans at end of year					$ 377,549	$ 0	$ 21,000
Allowance for loan losses		6,563	0	0	6,563	0	0
Balance of impaired loans not reserved					$ 370,986	$ 0	$ 21,000
Average impaired loans for the year		188,775	10,500	10,750
Interest recognized on impaired loans	[2]	$ 8,707	$ 0	$ 757

[1] Excludes direct write down of impaired loan receivable.

[2] Represents interest recognized prior to placement on non-accrual status.