Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Operating Activities:
Net earnings	$ 91,728	$ 92,663	$ 175,923	$ 173,273
Adjustments to reconcile net earnings to net cash from operating activities:
Provision for losses (recoveries) on accounts receivable	496	100	(619)	1,041
Deferred income tax expense	2,891	5,818	10,085	12,940
Excess tax benefits from stock plans	(495)	(584)	(984)	(1,683)
Stock compensation expense	11,877	11,040	22,171	22,045
Depreciation and amortization	12,417	11,674	24,799	22,952
Other	68	241	206	449
Changes in operating assets and liabilities:
Increase in accounts receivable	(84,618)	(48,223)	(72,390)	(9,367)
Increase in accounts payable and accrued expenses	61,377	45,080	90,923	43,690
Decrease in income taxes payable, net	(47,370)	(33,692)	(29,165)	(15,474)
Increase in other current assets	(3,485)	(91)	(2,206)	(576)
Net cash from operating activities	44,886	84,026	218,743	249,290
Investing Activities:
Purchase of short-term investments	(15,301)	(89,899)	(96,431)	(89,899)
Proceeds from maturities of short-term investments	15,643	96	36,619	134
Purchase of property and equipment	(9,635)	(17,141)	(18,395)	(27,209)
Escrow deposit for land acquisition	(27,101)	0	(27,101)	0
Other, net	(1,536)	1,264	134	820
Net cash from investing activities	(37,930)	(105,680)	(105,174)	(116,154)
Financing Activities:
Proceeds from issuance of common stock	22,125	7,548	30,017	18,477
Repurchases of common stock	(131,391)	(21,600)	(358,116)	(39,281)
Excess tax benefits from stock plans	495	584	984	1,683
Dividends paid	(62,807)	(61,899)	(62,807)	(61,899)
Purchase of noncontrolling interest	0	0	0	(7,730)
Distributions to noncontrolling interest	0	0	(85)	0
Net cash from financing activities	(171,578)	(75,367)	(390,007)	(88,750)
Effect of exchange rate changes on cash and cash equivalents	4,137	(11,557)	(653)	(19,119)
(Decrease) increase in cash and cash equivalents	(160,485)	(108,578)	(277,091)	25,267
Cash and cash equivalents at beginning of period	1,131,046	1,394,687	1,247,652	1,260,842
Cash and cash equivalents at end of period	970,561	1,286,109	970,561	1,286,109
Taxes Paid:
Income taxes	$ 105,963	$ 85,195	$ 133,459	$ 112,146