Real Estate Leases and Mortgage Notes Receivable (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Future minimum lease payments due to the Company under property operating agreements
2013	$ 4,390
2014	4,466
2015	4,535
2016	4,591
2017	4,634
2018 and thereafter	245,453
Total	268,069
Expiration Dates Through 2032 [Member]
Future minimum lease payments due to the Company under property operating agreements
2013	244,962
2014	209,284
2015	173,317
2016	145,453
2017	118,106
2018 and thereafter	446,027
Total	$ 1,337,149