CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands		Dec. 31, 2023	Dec. 31, 2022
Trade accounts receivable-billed, allowance		$ 5,432	$ 5,528
Property and equipment, accumulated depreciation		121,816	105,466
Customer contract costs, accumulated amortization		42,094	30,601
Long-term debt, unamortized discounts		$ 15,628	$ 2,656
Preferred stock, par value		$ 0.01	$ 0.01
Preferred stock, shares authorized		10,000,000	10,000,000
Preferred stock, shares issued		0	0
Preferred stock, shares outstanding		0	0
Common stock, par value		$ 0.01	$ 0.01
Common stock, shares authorized		100,000,000	100,000,000
Common stock, shares reserved for employee stock purchase plan and stock incentive plans		6,781,000	5,091,000
Common stock, shares outstanding		29,541,000	31,269,000
Treasury stock, shares		40,398	38,210
Software
Intangibles, accumulated amortization		$ 157,601	$ 150,337
Acquired customer contracts
Intangibles, accumulated amortization	[1]	$ 126,469	$ 120,080

[1] Acquired customer contracts represent assets acquired in our prior business acquisitions. Acquired customer contracts are amortized over their estimated useful lives ranging from three to twenty years based on the approximate pattern in which the economic benefits of the intangible assets are expected to be realized, with the amortization expense included as cost of revenue in our Income Statements.