Commitments and Contingencies (Concentrations of Risk) (Narrative) (Details) - customer			3 Months Ended		6 Months Ended
	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Concentration Risk [Line Items]
Number of customers					375
Credit Concentration Risk [Member] | Customer with Highest Net Accounts Receivable Position [Member] | Accounts Receivable, Net, Less Billings in Excess of Costs and Earnings [Member]
Concentration Risk [Line Items]
Number of customers	1
Concentration risk, percentage of total	20.00%	12.00%
Credit Concentration Risk [Member] | Customer with Second Highest Net Accounts Receivable Position [Member] | Accounts Receivable, Net, Less Billings in Excess of Costs and Earnings [Member]
Concentration Risk [Line Items]
Concentration risk, percentage of total	17.00%
Customer Concentration Risk [Member] | Ten Largest Customers [Member] | Revenue [Member]
Concentration Risk [Line Items]
Number of customers			10	10	10	10
Concentration risk, percentage of total			76.00%	60.00%	74.00%	59.00%