CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net income	$ 175,154	$ 158,920
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	11,347	12,006
Amortization of intangibles	56,364	42,425
Amortization of contract acquisition costs	14,700	14,059
Deferred income taxes	(1,477)	(945)
Employee share-based compensation expense	9,264	8,774
Loss on early debt extinguishment	0	8,917
Other non-cash items, net	3,128	1,197
Changes in assets and liabilities, net of effect of acquisitions:
Trade accounts receivable	5,320	13,970
Inventories and supplies	176	(1,368)
Other current assets	(2,379)	2,377
Non-current assets	(3,351)	(560)
Accounts payable	(1,619)	(12,547)
Contract acquisition payments	(17,190)	(9,843)
Other accrued and non-current liabilities	(41,316)	(18,234)
Net cash provided by operating activities	208,121	219,148
Cash flows from investing activities:
Purchases of capital assets	(32,215)	(29,549)
Payments for acquisitions, net of cash acquired	(64,637)	(50,933)
Proceeds from company-owned life insurance policies	4,123	3,973
Other	2,330	805
Net cash used by investing activities	(90,399)	(75,704)
Cash flows from financing activities:
Proceeds from short-term borrowings	0	50,000
Proceeds from issuing long-term debt	169,000	276,500
Payments on long-term debt, including costs of debt reacquisition	(185,873)	(375,291)
Proceeds from issuing shares under employee plans	6,861	5,492
Excess tax benefit from share-based employee awards	0	1,816
Employee taxes paid for shares withheld	(2,333)	(1,236)
Payments for common shares repurchased	(44,944)	(46,996)
Cash dividends paid to shareholders	(44,127)	(44,965)
Other	(1,634)	(378)
Net cash used by financing activities	(103,050)	(135,058)
Effect of exchange rate change on cash	2,966	(7,032)
Net change in cash and cash equivalents	17,638	1,354
Cash and cash equivalents, beginning of year	62,427	61,541
Cash and cash equivalents, end of period	$ 80,065	$ 62,895