CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net income	$ 58,215	$ 56,251
Adjustments to reconcile net income to cash provided (used) by operations:
Depreciation and amortization	37,521	11,586
Share-based compensation expense	21,348	14,459
Excess tax benefit from exercises of share-based arrangements	(18,816)	(10,801)
Deferred income tax (benefit) expense	(11,289)	643
Changes in operating assets and liabilities, exclusive of effects of acquired companies:
Accounts receivable	(14,641)	(14,356)
Income taxes	22,215	4,754
Prepaid expenses and other current assets	1,169	74
Accounts payable	(917)	(369)
Accrued liabilities	8,515	(3,349)
Deferred revenue	17,918	11,021
Net cash provided by operating activities	121,238	69,913
Cash flows from investing activities:
Additions to property and equipment	(29,529)	(8,525)
Purchase of marketable security investments	(13,127)	(29,391)
Proceeds from marketable security investments	9,256
Investment in Record Holdings Pty Limited		(15,000)
Cost of acquisitions, net of cash acquired	(9,394)	(6,447)
Increase (decrease) in other	(52)	5
Net cash used by investing activities	(42,846)	(59,358)
Cash flows from financing activities:
Decrease in net borrowings on revolving line of credit	(32,000)
Purchase of treasury shares	(94,499)	(645)
Proceeds from exercise of stock options	15,089	8,369
Contributions from employee stock purchase plan	4,429	3,367
Excess tax benefit from exercises of share-based arrangements	18,816	10,801
Net cash (used) provided by financing activities	(88,165)	21,892
Net (decrease) increase in cash and cash equivalents	(9,773)	32,447
Cash and cash equivalents at beginning of period	33,087	206,167
Cash and cash equivalents at end of period	$ 23,314	$ 238,614