Business Segment And Geographic Area Information (Narrative) (Details)	3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended			12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 Revenues [Member]	Jun. 30, 2012 Revenues [Member]	Jun. 30, 2013 Revenues [Member]	Jun. 30, 2012 Revenues [Member]	Jun. 30, 2013 Operating Income [Member]	Jun. 30, 2012 Operating Income [Member]	Jun. 30, 2013 Operating Income [Member]	Jun. 30, 2012 Operating Income [Member]	Jun. 30, 2013 Receivables [Member]	Dec. 31, 2012 Receivables [Member]
Segment Reporting Information [Line Items]
Number of reportable segments			1
Percentage of revenue from U.S. Government			99.00%	99.20%
Concentration Risk, Percentage	10.00%	10.00%	10.00%	10.00%	10.00%	10.00%	10.00%	10.00%	10.00%	10.00%	10.00%	10.00%	10.00%	10.00%