Real Estate Loans Receivable (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Advances on real estate loans receivable:
Investments in new loans		$ 12,091	$ 8,445	$ 530,497
Draws on existing loans		71,647	121,439	68,225
Net cash advances on real estate loans		83,738	129,884	598,722
Receipts On Real Estate Loans Receivable 1 [Abstract]
Loan payoffs		218,412	302,742	121,778
Principal Payments On Loans		1,219	6,867	33,340
Sub-total		219,631	309,609	155,118
Less : Non-cash activity	[1]	(123,608)	(60,057)	(23,288)
Net cash receipts on real estate loans		96,023	249,552	131,830
Net cash advances (receipts) on real estate loans		(12,285)	(119,668)	466,892
Change in balance due to foreign currency translation		9,136	(14,086)	(4,281)
Loan Impairment	[2]	0	(3,053)	0
Net Change Real Estate Loans Receivable		(126,757)	(196,864)	439,323
Summary of real estate loans receivable
Real estate loans receivable		495,871	622,628
Mortgage Receivable [Member]
Summary of real estate loans receivable
Real estate loans receivable		374,492	485,735
Other Real Estate Loans Receivables [Member]
Summary of real estate loans receivable
Real estate loans receivable		121,379	136,893
Outpatient Medical [Member]
Advances on real estate loans receivable:
Investments in new loans		0	0	0
Draws on existing loans		0	2,651	2,611
Net cash advances on real estate loans		0	2,651	2,611
Receipts On Real Estate Loans Receivable 1 [Abstract]
Loan payoffs		60,500	27,303	0
Principal Payments On Loans		0	0	0
Sub-total		60,500	27,303	0
Less : Non-cash activity	[1]	(60,500)	(15,013)	0
Net cash receipts on real estate loans		0	12,290	0
Net cash advances (receipts) on real estate loans		0	(9,639)	2,611
Change in balance due to foreign currency translation		0	0	0
Loan Impairment	[2]	0	(3,053)	0
Net Change Real Estate Loans Receivable		(60,500)	(27,705)	2,611
Triple Net [Member]
Advances on real estate loans receivable:
Investments in new loans		12,091	8,445	530,497
Draws on existing loans		71,647	118,788	65,614
Net cash advances on real estate loans		83,738	127,233	596,111
Receipts On Real Estate Loans Receivable 1 [Abstract]
Loan payoffs		157,912	275,439	121,778
Principal Payments On Loans		1,219	6,867	33,340
Sub-total		159,131	282,306	155,118
Less : Non-cash activity	[1]	(63,108)	(45,044)	(23,288)
Net cash receipts on real estate loans		96,023	237,262	131,830
Net cash advances (receipts) on real estate loans		(12,285)	(110,029)	464,281
Change in balance due to foreign currency translation		9,136	(14,086)	(4,281)
Loan Impairment	[2]	0	0	0
Net Change Real Estate Loans Receivable		$ (66,257)	$ (169,159)	$ 436,712

[1] Primarily represents aquisitions of assets previously financed as a real estate loans. Please see Note 3 for additional information.

[2] Represents a direct write down of an impaired loan receivable.