Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities:
Net earnings	$ 309,485	$ 327,053
Adjustments to reconcile net earnings to cash flows from operating activities:
Depreciation and amortization of property, plant and equipment	19,052	19,417
Amortization of intangible assets	99,719	78,758
Amortization of deferred financing costs	2,717	2,002
Non-cash stock compensation	39,092	29,438
Changes in operating assets and liabilities, net of acquired businesses:
Accounts receivable	(13,956)	40,860
Unbilled receivables	3,754	(11,172)
Inventories	(104)	(7,972)
Accounts payable and accrued liabilities	2,282	(3,623)
Income taxes payable	(77,931)	(36,257)
Other, net	(7,278)	(5,556)
Cash provided by operating activities	376,832	432,948
Cash flows from investing activities:
Acquisitions of businesses, net of cash acquired	(274,968)	(589,727)
Capital expenditures	(18,348)	(20,673)
Proceeds from sale of assets	758	594
Other, net	(679)	(4,522)
Cash used in investing activities	(293,237)	(614,328)
Cash flows from financing activities:
Borrowings/(payments) under revolving line of credit, net	(180,000)	315,000
Principal payments on convertible notes	(289)	(3,884)
Cash premiums paid on convertible note conversions	(915)	(12,721)
Debt issuance costs	(63)	0
Cash dividends to stockholders	(60,383)	(50,099)
Proceeds from stock based compensation, net	8,516	15,315
Stock award tax excess windfall benefit	0	8,781
Treasury stock sales	1,715	1,477
Other	(558)	(628)
Cash provided by/(used in) financing activities	(231,977)	273,241
Effect of foreign currency exchange rate changes on cash	(7,835)	(23,720)
Net increase/(decrease) in cash and cash equivalents	(156,217)	68,141
Cash and cash equivalents, beginning of period	778,511	610,430
Cash and cash equivalents, end of period	$ 622,294	$ 678,571