Notes Receivable and Allowance or Losses Past Due Balances Of Mezzanine And Other Notes Receivable (Details) (Notes Receivable [Member], USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Financing Receivable 30-89 days Past Due	$ 0	$ 0
Financing Receivable >90 days Past Due	9,676	9,773
Financing Receivable Total Past Due	9,676	9,773
Financing Receivable, Current	17,130	12,119
Total Receivables	26,806	21,892
Senior Notes [Member]
Financing Receivable 30-89 days Past Due	0	0
Financing Receivable >90 days Past Due	0	0
Financing Receivable Total Past Due	0	0
Financing Receivable, Current	11,191	7,900
Total Receivables	11,191	7,900
Senior Subordinated Notes [Member]
Financing Receivable 30-89 days Past Due	0	0
Financing Receivable >90 days Past Due	9,629	9,773
Financing Receivable Total Past Due	9,629	9,773
Financing Receivable, Current	5,355	4,219
Total Receivables	14,984	13,992
Unsecured Notes [Member]
Financing Receivable 30-89 days Past Due	0
Financing Receivable >90 days Past Due	47
Financing Receivable Total Past Due	47
Financing Receivable, Current	584
Total Receivables	$ 631