Transactions with Related Parties Related Party Ownership (Details)	Mar. 31, 2013 properties
Number of Variable Interest Entities	5
Total Owners [Member]
Number of Owners	4
Consolidated VIEs [Member]
Number of Variable Interest Entities	3
Consolidated VIEs [Member] | Total Owners [Member]
Number of Variable Interest Entities	3
Related party owner [Member] | Total Owners [Member]
Number of Owners	2