Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2019

Summary of Significant Accounting Policies [Abstract]

Disaggregation of Revenue

We have one reportable segment. We treat sales to U.S. customers as sales within the U.S. regardless of where the services are performed. Substantially all of our revenues are from U.S. customers as revenue derived from international customers is de minimus. The following tables disclose revenue (in thousands) by customer type and contract type for the periods presented.  Prior period amounts have not been adjusted under the modified retrospective method.

	2019		2018		2017
Federal	$	149,257	$	129,279	$	101,519
State & Local, and Commercial		9,961		8,737		6,208
Total	$	159,218	$	138,016	$	107,727

	2019		2018		2017
Firm fixed-price	$	131,629	$	103,454	$	89,516
Time-and-materials		14,569		16,795		10,222
Cost plus fixed fee		13,020		17,767		7,989
Total	$	159,218	$	138,016	$	107,727

Contract Assets and Liabilities

The following table discloses accounts receivable and contract assets (in thousands):

	December 31,
	2019			2018
Billed accounts receivable	$	11,917		$	18,848
Unbilled receivables		16,745			16,000
Allowance for doubtful accounts		(720	)		(306	)
Receivables – net	$	27,942		$	34,542

The following table discloses contract liabilities (in thousands):

	December 31,
	2019		2018
Contract liabilities	$	6,337	$	5,232

Allowance for Obsolescent Inventory

The components of the allowance for inventory obsolescence are set forth below (in thousands):

	Balance Beginning of Year		Additions Charge to Costs and Expense		Recoveries			Balance End of Year
Year Ended December 31, 2019	$	520	$	376	$	(36	)	$	860
Year Ended December 31, 2018	$	1,484	$	30	$	(994	)	$	520
Year Ended December 31, 2017	$	1,672	$	73	$	(261	)	$	1,484

Property and Equipment Useful Lives

Property and equipment is recorded at cost. Depreciation is provided using the straight-line method at rates based on the estimated useful lives of the individual assets or classes of assets as follows:

Furniture and equipment	3-5   Years
Leasehold improvements	Lesser of life of lease or useful life of asset
Property and equipment under finance leases	Lesser of life of lease or useful life of asset

Potentially Dilutive Securities not Included in Calculation of Diluted Net Loss per share

Potentially dilutive securities not included in the calculation of diluted net loss per share because to do so would be anti-dilutive are as follows (in common stock equivalent shares):

	2019		2018		2017
Unvested restricted stock		945		1,926		2,955
Common Stock Warrants, exercisable at $1.665/share		901		901		901
Total		1,846		2,827		3,856