Supplemental Cash Flow Information (Schedule of Cash and Cash Equivalents) (Details) - USD ($) $ in Thousands	Sep. 30, 2018		Dec. 31, 2017		Sep. 30, 2017	Dec. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Cash and Cash Equivalents	$ 24,412	[1]	$ 13,219	[1]	$ 39,246
Restricted Deposits and Mortgage Escrows	22,369		8,115		4,973
Total	$ 46,781		$ 21,334		$ 44,219	$ 41,279

[1] Consolidated variable interest entities' assets and debt included in the above balances (see Note 15) at September 30, 2018 and December 31, 2017 are Property, net of $200,276 and $207,969; Accrued Rent, Accrued Contract Receivables and Accounts Receivable, net of $11,239 and $12,011; Cash and Cash Equivalents of $8,989 and $9,025; Debt, net of $45,964 and $46,253.