Accounts Receivable and Unbilled Accounts Receivables (Details 3)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Transportation Security Administration [Member]
Percentage Of Accounts Receivable	19.00%	12.00%
Department Of Homeland Security [Member]
Percentage Of Accounts Receivable	16.00%	19.00%
Bureau Of Alcohol Tabacco And Firearms [Member]
Percentage Of Accounts Receivable	0.00%	10.00%