CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - UNAUDITED - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities:
Net income	$ 19,631	$ 21,514
Adjustments to reconcile net income to net cash used in operating activities -
Depreciation	6,113	5,565
Amortization	10,737	10,788
Amortization of original issue discount	772	730
Asset impairment	102	259
(Gain)/loss on short-term investments	15	(85)
Deferred income taxes	6,508	9,310
Stock-based compensation	5,395	4,857
Changes in operating assets and liabilities, net of acquired amounts:
Trade accounts receivable, net	(23,874)	(23,304)
Other current and non-current assets and liabilities	(999)	(8,452)
Income taxes payable/receivable	(1,022)	(3,092)
Trade accounts payable and accrued liabilities	(28,101)	(32,455)
Deferred revenue	1,914	7,152
Net cash used in operating activities	(2,809)	(7,213)
Cash flows from investing activities:
Purchases of software, property and equipment	(8,239)	(4,822)
Purchases of short-term investments	(32,304)	(16,037)
Proceeds from sale/maturity of short-term investments	29,340	18,670
Acquisition of and investments in business, net of cash acquired	(648)	(9,991)
Net cash used in investing activities	(11,851)	(12,180)
Cash flows from financing activities:
Proceeds from issuance of common stock	619	564
Payment of cash dividends	(8,635)	(8,277)
Repurchase of common stock	(11,738)	(13,876)
Payments on long-term debt	(2,813)	(1,875)
Net cash used in financing activities	(22,567)	(23,464)
Effect of exchange rate fluctuations on cash	(863)	(5,947)
Net decrease in cash and cash equivalents	(38,090)	(48,804)
Cash and cash equivalents, beginning of period	188,699	156,548
Cash and cash equivalents, end of period	150,609	107,744
Cash paid during the period for -
Interest	5,661	6,194
Income taxes	$ 1,468	$ 857