Orange County-Poughkeepsie Limited Partnership (Summarized O-P Balance Sheet Information) (Details) (O-P [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
O-P [Member]
Schedule of Equity Method Investments [Line Items]
Current assets	$ 20,788	$ 22,370
Property, plant and equipment, net	41,121	41,072
Total assets	61,909	63,442
Total liabilities	25,427	30,162
Partners' capital	36,482	33,280
Total liabilities and partners' capital	$ 61,909	$ 63,442