Non-Recourse Debt (Narratives) (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Additional Debt Disclosures
Mortgage notes payable, collateral	$ 2,900,000,000		$ 2,900,000,000		$ 2,900,000,000
Non-recourse mortgage loans	29,700,000		29,700,000
Debt, weighted average interest rate	4.40%		4.40%
Debt instrument terms (years)			6 years
Unamortized discount (premium), net	3,692,000		3,692,000
Foreign currency translation adjustments	(6,042,000)	8,612,000	(7,432,000)	(16,863,000)	29,884,000
Current Year Investments
Additional Debt Disclosures
Non-recourse mortgage loans	26,000,000		26,000,000
Prior Year Investments
Additional Debt Disclosures
Non-recourse mortgage loans	3,700,000		3,700,000
Non-recourse debt
Additional Debt Disclosures
Foreign currency translation adjustments			(2,900,000)
Debt Refinanced
Additional Debt Disclosures
Non-recourse mortgage loans	22,900,000		22,900,000
Debt, weighted average interest rate	7.30%		7.30%
Debt instrument terms (years)			14 years
Repayment of debt related to refinancing			(19,400,000)
Loss on extinguishment of debt			300,000
Minimum
Additional Debt Disclosures
Debt maturity date			Dec. 31, 2014
Maximum
Additional Debt Disclosures
Debt maturity date			Dec. 31, 2038
Real estate
Additional Debt Disclosures
Foreign currency translation adjustments			(5,600,000)
Real estate | Office Building in Tucson, AZ
Additional Debt Disclosures
Assumed non-recourse debt			10,300,000
Unamortized discount (premium), net	$ (1,300,000)		$ (1,300,000)
Fixed interest rate
Additional Debt Disclosures
Mortgage loan real estate, minimum interest rate			2.00%
Mortgage loan real estate, maximum interest rate			8.00%
Variable interest rate
Additional Debt Disclosures
Mortgage loan real estate, minimum interest rate			2.70%
Mortgage loan real estate, maximum interest rate			6.10%