Summary of Significant Accounting Policies (Details 2) (USD $)	3 Months Ended		3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014 Nonrecurring	Mar. 31, 2013 Nonrecurring	Mar. 31, 2014 Nonrecurring Total	Mar. 31, 2013 Nonrecurring Total	Mar. 31, 2014 Nonrecurring Level 2	Mar. 31, 2013 Nonrecurring Level 2	Mar. 31, 2014 Nonrecurring Level 3	Mar. 31, 2013 Nonrecurring Level 3
Assets at fair value and gains (losses) recorded
Inventory, Net	$ 3,257,000	$ 3,280,000			$ 3,257,000				$ 3,257,000
Equipment held for sale	30,376,000	32,491,000			30,376,000	23,996,000	19,844,000	23,966,000	10,532,000	30,000
Assets at fair value					33,633,000	23,996,000	19,844,000	23,966,000	13,789,000	30,000
Total losses on inventory	(295,000)
Total losses on assets	(295,000)
Asset write-down recorded earlier			$ 300,000	$ 0