Orange County-Poughkeepsie Limited Partnership (Summarized O-P Balance Sheet Information) (Details) (O-P [Member], USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
O-P [Member]
Schedule of Equity Method Investments [Line Items]
Current assets	$ 22,370	$ 20,525
Property, plant and equipment, net	41,072	39,596
Total assets	63,442	60,121
Total liabilities	30,162	42,500
Partners' capital	33,280	17,621
Total liabilities and partners' capital	$ 63,442	$ 60,121