Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 107,298	$ 41,279
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of intangible assets	118	362
Depreciation expense	38,509	42,370
Stock-based compensation expense-restricted stock and stock units	38,193	43,043
Stock-based compensation expense-stock options		170
Excess tax benefits from stock-based compensation	(1,087)	(917)
Provision for deferred income taxes	(7,186)	(14,948)
Provision for doubtful accounts receivable	3,940	5,407
Changes in assets and liabilities:
Increase in accounts receivable	(99,490)	(71,189)
Increase in accounts payable, accrued expenses, accrued payroll costs and retirement obligations	56,280	24,531
Increase in income taxes payable	30,701	19,773
Change in other assets, net of change in other liabilities	(7,608)	11,592
Net cash flows provided by operating activities	159,668	101,473
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(41,708)	(22,049)
Decrease in trusts for employee benefits and retirement plans	(4,812)	(612)
Net cash flows used in investing activities	(46,520)	(22,661)
CASH FLOWS FROM FINANCING ACTIVITIES:
Repurchases of common stock	(140,391)	(83,188)
Cash dividends paid	(60,024)	(57,612)
Decrease in notes payable and other indebtedness	(92)	(84)
Excess tax benefits from stock-based compensation	1,087	917
Proceeds from exercises of stock options	15,279	6,077
Net cash flows used in financing activities	(184,141)	(133,890)
Effect of exchange rate changes on cash and cash equivalents	(1,418)	340
Net decrease in cash and cash equivalents	(72,411)	(54,738)
Cash and cash equivalents at beginning of period	315,137	365,794
Cash and cash equivalents at end of period	242,726	311,056
Cash paid during the period for:
Interest	409	454
Income taxes, net of refunds	$ 44,857	$ 23,537