Fair Value Measurements - Schedule of Carrying Amount And Estimated Fair Value Of Financial Instruments (Details) - USD ($)
$ in Thousands
Mar. 31, 2015
Dec. 31, 2014
Carrying Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Loans receivable, net $ 107,403 $ 109,425
Revolving Credit Facilities 181,518 15,114
Mortgages and notes payable, net 3,456,609 3,629,998
Convertible Notes, net 681,109 678,190
Estimated Fair Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Loans receivable, net 113,495 115,747
Revolving Credit Facilities 185,212 15,254
Mortgages and notes payable, net 3,697,971 3,899,950
Convertible Notes, net $ 747,589 $ 729,231