CONDENSED CONSOLIDATED BALANCE SHEETS - UNAUDITED (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Trade accounts receivable-billed, allowance	$ 4,924	$ 4,250
Property and equipment, accumulated depreciation	114,393	111,244
Intangibles, accumulated amortization	272,216	266,449
Customer costs, accumulated amortization	35,860	32,410
Long-term debt, unamortized discounts	$ 3,218	$ 3,406
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 outstanding	32,560,000	32,495,000
Treasury stock, shares	36,979,000	36,713,000
Software
Intangibles, accumulated amortization	$ (156,490)	$ (152,283)
Acquired customer contracts
Intangibles, accumulated amortization	$ (115,726)	$ (114,166)