Summary of Significant Accounting Policies, Line Items Adjusted Upon Adoption (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Revenue	$ 92,249	$ 92,249	$ 70,880	[1]
Gross profit	23,130	23,130	18,544
Provision for income taxes	1,131	1,131	(6,153)
Net loss	$ (354)	$ (354)	$ 6,557
Basic loss per common share (in dollars per share)	$ (0.02)	$ (0.02)	$ 0.34
Diluted loss per common share (in dollars per share)		$ (0.02)	$ 0.33
Balance Sheet [Abstract]
Contract receivables, net	$ 21,077	$ 21,077
Deferred tax assets	5,461	5,461	$ 6,494
Billings in excess of revenue earned	10,609	10,609	14,543
Accumulated deficit	(42,569)	(42,569)	$ (42,870)
Effect of Change [Member]
Income Statement [Abstract]
Revenue	(474)
Gross profit	(474)
Provision for income taxes	126
Net loss	(348)
Balance Sheet [Abstract]
Contract receivables, net	0	0
Deferred tax assets	(115)	(115)
Billings in excess of revenue earned	(479)	(479)
Accumulated deficit	364	364
Balance Without Adoption of ASC 606 [Member]
Income Statement [Abstract]
Revenue	92,723
Gross profit	23,604
Provision for income taxes	1,257
Net loss	$ (6)
Basic loss per common share (in dollars per share)	$ 0
Diluted loss per common share (in dollars per share)	$ 0
Balance Sheet [Abstract]
Contract receivables, net	$ 21,077	21,077
Deferred tax assets	5,576	5,576
Billings in excess of revenue earned	11,088	11,088
Accumulated deficit	$ (42,933)	$ (42,933)

[1] Prior period amounts have not been adjusted under the modified retrospective transition method for the adoption of ASC 606.