Notes Payable, Interest Expense and Commitments and Contingencies (Interest Expense) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Detail of interest expensed and incurred
Total interest incurred	$ 6,364	$ 7,358	$ 13,058	$ 14,902
Interest capitalized	489	0	915	0
Total interest expense	$ 5,875	$ 7,358	$ 12,143	$ 14,902