Summary of Significant Accounting Policies (Concentration Risk) (Details) (Accounts Receivable [Member])	12 Months Ended
	Dec. 31, 2012 Customers	Dec. 31, 2011
Concentration Risk [Line Items]
Number of customers	2
Net accounts receivable held by major customers		40.00%
Benchmark for concentration risk	No other customers accounted for more than 10% of net accounts receivable
Customer One [Member]
Concentration Risk [Line Items]
Net accounts receivable held by major customers	26.00%
Customer Two [Member]
Concentration Risk [Line Items]
Net accounts receivable held by major customers	12.00%