Condensed Consolidated Statements of Cash Flows (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Operating Activities:
Net earnings	$ 106,876	$ 96,038	$ 293,103	$ 247,757
Adjustments to reconcile net earnings to net cash provided by operating activities:
Provision for losses on accounts receivable	(629)	1,284	1,161	3,109
Deferred income tax (benefit) expense	(9,328)	(565)	(9,663)	2,521
Excess tax benefits from stock plans	(537)	(3,470)	(5,068)	(11,589)
Stock compensation expense	12,738	10,846	33,446	33,047
Depreciation and amortization	9,199	9,085	27,630	27,590
Gain on sale of assets	(3)	(57)	(54)	(461)
Other	1,210	387	1,828	1,232
Changes in operating assets and liabilities:
Increase in accounts receivable	(4,312)	(34,203)	(11,802)	(266,770)
Increase in other current assets	(8,344)	(4,095)	(5,863)	(2,959)
(Decrease) increase in accounts payable and accrued expenses	(24,070)	25,330	14,060	190,440
Increase in income taxes payable, net	10,505	12,438	10,417	36,770
Net cash provided by operating activities	93,305	113,018	349,195	260,687
Investing Activities:
Decrease in short-term investments, net	561	137	23	107
Purchase of property and equipment	(20,619)	(10,953)	(58,854)	(26,653)
Proceeds from sale of property and equipment	24	98	109	268
Other	(1,193)	1,208	(2,699)	313
Net cash used in investing activities	(21,227)	(9,510)	(61,421)	(25,965)
Financing Activities:
Proceeds from issuance of common stock	30,966	37,718	54,591	60,958
Repurchases of common stock	(43,298)	(67,782)	(108,572)	(139,450)
Excess tax benefits from stock plans	537	3,470	5,068	11,589
Dividends paid	0	0	(53,014)	(42,397)
Distributions to noncontrolling interest	(822)	(963)	(822)	(963)
Net cash used in financing activities	(12,617)	(27,557)	(102,749)	(110,263)
Effect of exchange rate changes on cash and cash equivalents	(24,477)	20,975	(8,676)	6,838
Increase in cash and cash equivalents	34,984	96,926	176,349	131,297
Cash and cash equivalents at beginning of period	1,225,830	960,300	1,084,465	925,929
Cash and cash equivalents at end of period	1,260,814	1,057,226	1,260,814	1,057,226
Interest and Taxes Paid:
Interest	48	9	65	53
Income taxes	$ 65,856	$ 52,407	$ 183,167	$ 129,249

Name:	us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 7

-Footnote 1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3044-108585

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 8, 9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6361293&loc=d3e6676-107765

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 7, 26

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016