CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Cash Flows [Abstract]
Net income	$ 8,881	$ 28,705	$ 56,604
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	44,770	34,249	23,073
Unrealized (gain) loss and impairment of equity investment	0	5,948	(5,433)
Stock-based compensation	28,862	20,646	14,107
Provision for doubtful accounts	5,675	0	0
Deferred income taxes	(13,406)	(7,166)	4,753
Accretion of discount on marketable securities	(4,093)	(577)	(45)
Non-cash lease expense	6,145	5,831	2,042
Other	45	90	45
Changes in operating assets and liabilities:
Accounts receivable	(75,716)	(24,408)	(67,405)
Prepaid expenses and other current assets	3,918	(1,595)	(7,681)
Accounts payable	79,687	29,763	68,301
Accrued liabilities	3,035	(1,024)	3,530
Operating lease liabilities	(5,789)	(5,539)	(2,283)
Other liabilities, non-current	(893)	2,289	(927)
Net cash provided by operating activities	81,121	87,212	88,681
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of and deposits on property and equipment	(10,601)	(35,869)	(30,432)
Capitalized software development costs	(17,687)	(13,024)	(8,929)
Purchases of marketable securities	(140,603)	(137,793)	(90,562)
Proceeds from sales of marketable securities	18,873	0	0
Proceeds from maturities of marketable securities	111,000	133,400	33,200
Business combination, net of cash acquired	0	(28,085)	0
Net cash used in investing activities	(39,018)	(81,371)	(96,723)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from initial public offering, net of underwriting discounts and commissions	0	0	(806)
Proceeds from issuance of common stock for employee stock purchase plan	1,869	2,960	4,804
Proceeds from exercise of stock options	1,549	1,195	5,423
Principal payments on finance lease obligations	(126)	(119)	(10)
Payments to acquire treasury stock	(59,268)	0	(52)
Net cash provided by (used in) financing activities	(55,976)	4,036	9,359
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(13,873)	9,877	1,317
CASH AND CASH EQUIVALENTS - Beginning of Year	92,382	82,505	81,188
CASH AND CASH EQUIVALENTS - End of Year	78,509	92,382	82,505
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Income taxes paid	15,631	9,190	6,786
SUPPLEMENTAL DISCLOSURES OF NON-CASH INVESTING AND FINANCING INFORMATION:
Stock-based compensation capitalized as internal use software costs	2,462	1,475	903
Property and equipment included in accounts payable and accrued expenses	203	749	49
Capitalized software costs included in accounts payable and accrued expenses	2,966	1,796	1,794
Business combination purchase consideration - indemnification claims holdback	$ 2,148	$ 2,148	$ 0