Revenue and Accounts Receivable (Tables)

12 Months Ended

Dec. 31, 2016

Revenue and Accounts Receivable [Abstract]

Accounts Receivable Components

The components of accounts receivable are as follows (in thousands):

	December 31,
	2016			2015
Billed accounts receivable	$	13,164		$	15,340
Unbilled receivables		6,352			4,190
Allowance for doubtful accounts		(429	)		(485	)
	$	19,087		$	19,045

       The activities in the allowance for doubtful accounts are set forth below (in thousands):

Allowance for Doubtful Accounts

	Balance Beginning of Year		Bad Debt Expenses (1)			Recoveries (2)		Balance End of Year
Year Ended December 31, 2016	$	485	$	(56	)	$	--	$	429
Year Ended December 31, 2015	$	372	$	113		$	--	$	485
Year Ended December 31, 2014	$	321	$	51		$	--	$	372

                    (1)          Accounts receivable reserves and reversal of allowance for subsequent collections, net

                    (2)          Accounts receivable written-off and subsequent recoveries, net

Revenue by Customer Sector

We derived substantially all of our revenues from contracts and subcontracts with the U.S. Government. Revenue by customer sector for the last three fiscal years is as follows:

	2016				2015				2014
					(dollar amounts in thousands)
Federal	$	130,415	96.7	%	$	117,328	97.3	%	$	122,549	96.1	%
State & Local, and Commercial		4,453	3.3	%		3,306	2.7	%		5,013	3.9	%
Total	$	134,868	100.0	%	$	120,634	100.0	%	$	127,562	100.0	%