CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net income	$ 66,130	$ 61,364	$ 62,882
Adjustments to reconcile net income to net cash provided by operating activities-
Depreciation	18,304	13,380	13,616
Amortization	44,328	29,501	27,626
Amortization of original issue discount	2,664	2,790	4,866
Asset impairment	1,851	3,135
Gain on short-term investments and other	(101)	(184)	(83)
Loss on extinguishment of debt	810		8,651
Gain on disposition of business operations			(6,611)
Deferred income taxes	4,913	7,112	(2,811)
Excess tax benefit of stock-based compensation awards			(4,729)
Stock-based compensation	19,358	21,049	22,715
Changes in operating assets and liabilities, net of acquired amounts:
Trade accounts receivable, net	(138)	(6,421)	(23,243)
Other current and non-current assets and liabilities	(23,179)	2,875	255
Income taxes payable/receivable	5,055	(2,729)	(14,167)
Trade accounts payable and accrued liabilities	(7,146)	(4,377)	(5,738)
Deferred revenue	10,492	(300)	957
Net cash provided by operating activities	143,341	127,195	84,186
Cash flows from investing activities:
Purchases of software, property and equipment	(57,104)	(28,942)	(14,263)
Purchases of short-term investments	(75,022)	(182,247)	(196,967)
Proceeds from sale/maturity of short-term investments	190,778	193,465	157,825
Acquisition of and investments in business, net of cash acquired	(144,791)
Acquisition of and investments in client contracts		(12,180)	(7,587)
Proceeds from the disposition of business operations			8,850
Net cash used in investing activities	(86,139)	(29,904)	(52,142)
Cash flows from financing activities:
Proceeds from issuance of common stock	2,311	1,776	1,547
Payment of cash dividends	(27,979)	(26,850)	(24,110)
Repurchase of common stock	(34,726)	(30,649)	(25,196)
Proceeds from long-term debt	150,000		230,000
Payments on long-term debt	(125,625)	(15,000)	(7,500)
Repurchase of convertible notes			(215,676)
Excess tax benefit of stock-based compensation awards			4,729
Settlement of convertible notes		(34,771)
Payments of deferred financing costs	(1,490)		(6,744)
Net cash used in financing activities	(37,509)	(105,494)	(42,950)
Effect of exchange rate fluctuations on cash	(2,659)	4,095	4,626
Net increase (decrease) in cash and cash equivalents	17,034	(4,108)	(6,280)
Cash and cash equivalents, beginning of period	122,243	126,351	132,631
Cash and cash equivalents, end of period	139,277	122,243	126,351
Cash paid during the period for-
Interest	15,857	14,729	12,191
Income taxes	$ 10,426	$ 22,144	$ 53,020