Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net income	$ 30,971,000	$ 31,800,000	$ 37,466,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and impairment	5,899,000	5,277,000	6,374,000
Reclassification of cumulative translation adjustment into earnings	(0)	2,569,000	(0)
Deferred income taxes	(1,121,000)	(1,729,000)	(277,000)
Reserve for uncertain tax positions	404,000	488,000	310,000
Loss on disposal of property and equipment	0	11,000	7,000
Non-cash share-based compensation expense	935,000	1,200,000	623,000
Change in assets and liabilities:
Trade accounts receivable	2,084,000	(733,000)	343,000
Prepaid expenses and other current and long-term assets	(1,767,000)	1,634,000	(842,000)
Operating lease assets and liability, net	(127,000)	(39,000)	(34,000)
Deferred contract costs, net	988,000	1,331,000	783,000
Accounts payable	184,000	(589,000)	4,000
Accrued expenses, wages and bonuses	(768,000)	(2,947,000)	(285,000)
Income taxes receivable and payable	795,000	6,000	484,000
Deferred revenue	(364,000)	(2,014,000)	1,388,000
Net cash provided by operating activities	38,113,000	36,265,000	46,344,000
Cash flows from investing activities:
Purchases of property and equipment	(15,779,000)	(9,835,000)	(5,514,000)
Acquisition consideration	0	0	(3,000,000)
Proceeds from the sale of property and equipment	1,000	0	0
Net cash used in investing activities	(15,778,000)	(9,835,000)	(8,514,000)
Cash flows from financing activities:
Payments on notes payable	(4,528,000)	(4,305,000)	(4,093,000)
Payment of debt issuance costs	(8,000)	(92,000)	0
Borrowings on notes payable	19,000,000	0	0
Borrowings on line of credit	15,000,000	0	0
Payments on line of credit	(15,000,000)	0	0
Payments on finance lease obligations	(290,000)	(469,000)	(493,000)
Proceeds from the exercise of stock options	584,000	0	446,000
Payment of payroll tax withholdings on share-based awards exercised	0	(190,000)	(721,000)
Payment of deferred acquisition consideration	0	(1,950,000)	0
Repurchase of shares for treasury	(19,099,000)	(27,616,000)	(4,142,000)
Payment of dividends on common stock	(36,366,000)	(20,961,000)	(9,159,000)
Net cash used in financing activities	(40,707,000)	(55,583,000)	(18,162,000)
Effect of exchange rate changes on cash	(1,000)	(182,000)	3,000
Net increase (decrease) in cash and cash equivalents	(18,373,000)	(29,335,000)	19,671,000
Cash and cash equivalents at beginning of period	25,026,000	54,361,000	34,690,000
Cash and cash equivalents at end of period	6,653,000	25,026,000	54,361,000
Supplemental disclosure of cash paid for:
Interest expense, net of capitalized amounts	803,000	1,227,000	1,684,000
Income taxes	8,932,000	12,233,000	10,644,000
Supplemental disclosure of non-cash investing and financing activities:
Finance lease obligations originated for property and equipment	0	0	40,000
Purchase of property and equipment in accounts payable and accrued expenses	2,066,000	1,109,000	979,000
Stock tendered to the Company for cashless exercise of stock options in connection with equity incentive plans	1,241,000	311,000	1,088,000
Repurchase of shares for treasury in accounts payable and accrued expenses	152,000	0	0
Deferred acquisition consideration	$ 0	$ 0	$ 1,950,000