Non-Recourse Property Debt and Credit Agreement (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Scheduled principal amortization and maturity payments
Amortization, 2014	$ 88,010
Amortization, 2015	88,424
Amortization, 2016	85,380
Amortization, 2017	79,223
Amortization, 2018	74,232
Maturities, 2014	82,192
Maturities, 2015	183,317
Maturities, 2016	465,321
Maturities, 2017	398,320
Maturities, 2018	238,253
Total Amortization and Maturities, 2014	170,202
Total Amortization and Maturities, 2015	271,741
Total Amortization and Maturities, 2016	550,701
Total Amortization and Maturities, 2017	477,543
Total Amortization and Maturities, 2018	312,485
Total Amortization and Maturities, Thereafter	2,555,113
Principal outstanding	$ 4,337,785	$ 4,413,083