Fair Value Measurements Assets and Liabilities Measured on a Non-Recurring Basis (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Valuation Adjustments To Inventory	$ 900	$ 3,112
Valuation Adjustments To Investments In Unconsolidated Entities	0	390
Total losses	900	3,502
Fair Value, Inputs - Quoted Prices in Active Markets for Identical Assets, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Inventory	0	0
Investments in Unconsolidated LLCs	0	0
Total fair value measurements	0	0
Fair Value, Significant Other observable Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Inventory	0	0
Investments in Unconsolidated LLCs	0	0
Total fair value measurements	0	0
Fair Value, Significant Unobservable Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Inventory	2,015	5,608
Investments in Unconsolidated LLCs	0	1,050
Total fair value measurements	2,015	6,658
Total Fair Value Measurements - Non-Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Inventory	2,015	5,608
Investments in Unconsolidated LLCs	0	1,050
Total fair value measurements	$ 2,015	$ 6,658