Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities
Net income	$ 55,419	$ 75,126	$ 85,377
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	64,250	59,567	64,974
Amortization of debt issue costs and accretion of discount	5,128	4,334	3,329
Loss on extinguishment of debt	0	1,476	0
Provision for doubtful accounts and sundry losses	843	1,990	2,130
Deferred tax benefit	(4,306)	(4,594)	(3,090)
Share-based compensation	9,642	6,408	5,204
Loss on impairment of software	11,441	2,277	0
Loss on disposition of property and equipment and other intangibles	430	453	143
(Earnings) losses of equity method investment	(604)	52	(147)
(Increase) decrease in assets:
Accounts receivable	(2,099)	(2,583)	(4,482)
Prepaid expenses and other assets	(4,048)	(1,426)	(146)
Other long-term assets	1,654	(1,790)	(70)
Increase (decrease) in liabilities:
Accounts payable and accrued liabilities	(870)	14,594	15,947
Income tax payable	(349)	405	(606)
Unearned income	8,444	8,018	2,207
Other long-term liabilities	811	3,747	(8,351)
Total adjustments	90,367	92,928	77,042
Net cash provided by operating activities	145,786	168,054	162,419
Cash flows from investing activities
Net (increase) decrease in restricted cash	(1,832)	3,705	(6,100)
Additions to software and purchase of customer relationship	(22,174)	(23,819)	(25,960)
Acquisitions, net of cash acquired	(42,836)	(15,600)	0
Property and equipment acquired	(11,290)	(18,450)	(21,022)
Proceeds from sales of property and equipment	32	81	14
Net cash used in investing activities	(78,100)	(54,083)	(53,068)
Cash flows from financing activities
Proceeds from issuance of long-term debt	0	75,763	0
Debt issuance costs	0	(4,830)	0
Net (decrease) increase in short-term borrowings	(16,000)	11,000	(6,000)
Repayments of borrowings for purchase of equipment and software	(2,373)	(2,213)	(1,542)
Dividends paid	(21,762)	(29,696)	(30,921)
Withholding taxes paid on share-based compensation	(1,588)	(548)	(306)
Repurchase of common stock	(7,671)	(39,946)	(54,949)
Repayment of long-term debt	(19,789)	(96,741)	(19,000)
Credit amendment fees	0	(3,587)	0
Net cash used in financing activities	(69,183)	(90,798)	(112,718)
Net (decrease) increase in cash and cash equivalents	(1,497)	23,173	(3,367)
Cash and cash equivalents at beginning of the period	51,920	28,747	32,114
Cash and cash equivalents at end of the period	50,423	51,920	28,747
Supplemental disclosure of cash flow information:
Cash paid for interest	25,379	22,535	21,497
Cash paid for income taxes	9,930	8,697	5,682
Supplemental disclosure of non-cash activities:
Payable due to vendor related to property and equipment and software acquired	$ 1,037	$ 3,302	$ 3,638