UNAUDITED QUARTERLY OPERATING RESULTS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues:	$ 87,074	$ 90,385	$ 91,566	$ 85,180	$ 78,649	$ 87,028	$ 92,498	$ 86,725	$ 354,205	$ 344,900	$ 336,508
Operating expenses
Selling & administrative and product support	8,727	8,153	8,356	9,964	8,462	8,514	8,268	7,503
Enterprise technology & product support	6,917	6,743	6,745	6,445	6,386	6,176	5,735	5,647
Depreciation & amortization	3,535	3,524	3,130	2,421	2,466	2,441	2,145	2,065	12,610	9,117	6,929
Total operating expenses	75,330	72,414	73,837	70,205	66,080	67,581	70,094	66,085	291,786	269,840	258,171
Operating income (loss)	11,744	17,971	17,729	14,975	12,569	19,447	22,404	20,640	62,419	75,060	78,337
Interest income	604	729	577	604	406	153	57	0	2,514	616	0
Income before income taxes	12,348	18,700	18,306	15,579	12,975	19,600	22,461	20,640	64,933	75,676	78,337
Income tax provision	2,390	4,190	3,846	4,077	3,127	3,698	5,450	5,132	14,503	17,407	26,723
Net income	$ 9,958	$ 14,510	$ 14,460	$ 11,502	$ 9,848	$ 15,902	$ 17,011	$ 15,508	$ 50,430	$ 58,269	$ 51,614
Basic net income per share (in usd per share)	$ 0.15	$ 0.21	$ 0.21	$ 0.17	$ 0.15	$ 0.24	$ 0.25	$ 0.23	$ 0.75	$ 0.87	$ 0.77
Diluted net income per share (in usd per share)	$ 0.15	$ 0.21	$ 0.21	$ 0.17	$ 0.15	$ 0.24	$ 0.25	$ 0.23	$ 0.75	$ 0.87	$ 0.77
Weighted average shares outstanding
Basic (in shares)	66,967	66,960	66,940	66,670	66,569	66,562	66,541	66,323	66,884	66,499	66,209
Diluted (in shares)	66,967	66,960	66,940	66,670	66,641	66,598	66,561	66,323	66,884	66,560	66,266
Software & services
Revenues:	$ 7,542	$ 9,301	$ 8,737	$ 7,925	$ 6,295	$ 6,144	$ 5,943	$ 5,934	$ 33,505	$ 24,316	$ 25,157
Operating expenses
State enterprise cost of revenues, exclusive of depreciation & amortization	3,797	3,586	3,329	2,720	2,354	2,226	2,235	2,228	13,432	9,043	8,890
State Enterprise Revenues
Revenues:	79,532	81,084	82,829	77,255	72,354	80,884	86,555	80,791	320,700	320,584	311,351
Operating expenses
State enterprise cost of revenues, exclusive of depreciation & amortization	$ 52,354	$ 50,408	$ 52,277	$ 48,655	$ 46,412	$ 48,224	$ 51,711	$ 48,642	$ 203,694	$ 194,989	$ 191,572