Non-Recourse and Limited Recourse Debt (Details 1) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Long-term Debt, by Maturity
2013 (remainder)	$ 50,832
2014	37,136
2015	66,817
2016	287,607
2017	339,559
Thereafter through 2038	930,378
Long-term Debt	1,712,329
Unamortized discount, net	(7,343)
Total	$ 1,704,986	$ 1,633,452

The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

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