Revenue and Accounts Receivable (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Accounts Receivable [Line Items]
Concentration risk, percentage (in hundredths)									100.00%		100.00%		100.00%
Components of Accounts Receivable [Abstract]
Billed accounts receivable	$ 21,476								$ 29,492		$ 21,476
Unbilled receivables	12,722								16,461		12,722
Allowance for doubtful accounts	(319)				(375)				(321)		(319)		(375)
Accounts Receivable, Net, Total	33,879								45,632		33,879
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance Beginning of Year				375				358	319		375		358
Bad Debt Expenses									2	[1]	(53)	[1]	17	[1]
Deductions									0	[2]	(3)	[2]	0	[2]
Balance End of Year	319				375				321		319		375
Revenue by Customer Sector [Abstract]
Revenue	55,323	49,279	55,214	47,578	48,413	66,916	56,338	54,429	207,394		226,096		189,888
Federal [Member]
Accounts Receivable [Line Items]
Concentration risk, percentage (in hundredths)									98.30%		99.10%		99.10%
Revenue by Customer Sector [Abstract]
Revenue									203,917		224,010		188,162
Federal [Member] | Revenue from Contracts and Subcontracts [Member]
Accounts Receivable [Line Items]
Concentration risk, percentage (in hundredths)									98.30%		99.10%		99.10%
Federal [Member] | Accounts Receivable [Member]
Accounts Receivable [Line Items]
Concentration risk, percentage (in hundredths)									95.00%
Commercial [Member]
Accounts Receivable [Line Items]
Concentration risk, percentage (in hundredths)									1.70%		0.90%		0.90%
Revenue by Customer Sector [Abstract]
Revenue									$ 3,477		$ 2,086		$ 1,726

[1] Accounts receivable reserves and reversal of allowance for subsequent collections, net

[2] Accounts receivable written-off and subsequent recoveries, net