Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities:
Cash received from customers	$ 2,018,755	$ 1,877,483	$ 1,778,316
Cash paid to suppliers and employees	(1,656,467)	(1,536,935)	(1,386,382)
Interest paid	(56,859)	(59,834)	(38,471)
Income tax payments	(52,131)	(55,502)	(37,749)
Investment proceeds and miscellaneous receipts, net	9,686	3,625	10,024
Excess tax benefits from share-based compensation	(3,168)	(2,928)	(664)
Net cash provided by operating activities	259,816	225,909	325,074
Cash flows from investing activities:
Capital expenditures	(102,888)	(88,453)	(68,044)
Proceeds from sale of property, plant and equipment	234	1,190	1,249
Payments for acquisitions, net of cash received, and long-term investments	(158,538)	(89,307)	(35,990)
Payments on purchases of intangible assets	(436)	(4,081)	(9,566)
Purchases of marketable securities and investments	(509,310)	(240,286)	(147,554)
Sales of marketable securities and investments	48,825	4,193	7,746
Maturities of marketable securities and investments	335,781	203,443	78,727
Proceeds from (payments for) foreign currency economic hedges, net	2,919	3,211	(2,520)
Restricted cash	0	(6,422)	0
Net cash used in investing activities	(383,413)	(216,512)	(175,952)
Cash flows from financing activities:
Net payments on line-of-credit arrangements and notes payable	(3,900)	(830)	(2,303)
Long-term borrowings	0	424,633	294,750
Payments on long-term borrowings	(226,835)	(206,706)	(6,823)
Proceeds from issuance of common stock	14,249	12,730	10,286
Debt issuance costs on long-term borrowings	(242)	(4,010)	(2,641)
Excess tax benefits from share-based compensation	3,168	2,928	664
Net cash (used in) provided by financing activities	(213,560)	228,745	293,933
Effect of foreign exchange rate changes on cash	4,837	18,471	2,359
Net (decrease) increase in cash and cash equivalents	(332,320)	256,613	445,414
Cash and cash equivalents at beginning of year	906,551	649,938	204,524
Cash and cash equivalents at end of year	$ 574,231	$ 906,551	$ 649,938