CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities:
Net income	$ 35,951	$ 36,109
Adjustments to reconcile net income to cash provided (used) by operations:
Depreciation and amortization	24,850	7,484
Share-based compensation expense	13,692	8,861
Excess tax benefit from exercises of share-based arrangements	(6,694)	(8,827)
Changes in operating assets and liabilities, exclusive of effects of acquired companies:
Accounts receivable	(35,530)	(36,624)
Income taxes	4,207	2,735
Prepaid expenses and other current assets	(1,435)	(549)
Accounts payable	(236)	(371)
Accrued liabilities	4,883	(5,685)
Deferred revenue	14,459	11,680
Net cash provided by operating activities	54,147	14,813
Cash flows from investing activities:
Additions to property and equipment	(21,959)	(6,126)
Purchase of marketable security investments	(10,607)	(6,449)
Proceeds from marketable security investments	6,526
Investment in Record Holdings Pty Limited		(15,000)
Cost of acquisitions, net of cash acquired	(9,394)	(6,447)
Increase in other	(281)	(9)
Net cash used by investing activities	(35,715)	(34,031)
Cash flows from financing activities:
Increase in net borrowings on revolving line of credit	69,000
Purchase of treasury shares	(94,497)	(645)
Proceeds from exercise of stock options	5,793	6,729
Contributions from employee stock purchase plan	2,818	2,243
Excess tax benefit from exercises of share-based arrangements	6,694	8,827
Net cash (used) provided by financing activities	(10,192)	17,154
Net increase (decrease) in cash and cash equivalents	8,240	(2,064)
Cash and cash equivalents at beginning of period	33,087	206,167
Cash and cash equivalents at end of period	$ 41,327	$ 204,103