CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Cash flows from operating activities:
Net income	$ 70,380	$ 70,806
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	51,699	51,000
Non-cash compensation expense associated with employee benefit and stock compensation plans	18,939	16,215
Deferred income tax benefit	(3,828)	(5,752)
Loss on disposal of property and equipment	344	345
Equity investee loss (earnings)	242	(673)
Changes in operating assets and liabilities:
Accounts receivable	(36,544)	4,013
Unbilled services	(16,948)	(16,830)
Inventory	(6,075)	3,302
Accounts payable	10,611	(1,141)
Accrued liabilities	17,838	(19,636)
Unearned revenue	2,027	(14,817)
Income taxes payable	(17,811)	3,994
Other assets and liabilities, net	(2,142)	(9,454)
Net cash provided by operating activities	88,732	81,372
Cash flows from investing activities:
Capital expenditures	(50,548)	(67,461)
Other, net	106	50
Net cash used in investing activities	(50,442)	(67,411)
Cash flows from financing activities:
Net repayments under revolving credit facility	(35,000)	0
Repayments under long-term debt	(5,000)	0
Stock issued under employee stock purchase and option plans	7,622	9,270
Purchase of treasury stock	(7,517)	(5,283)
Net cash (used in) provided by financing activities	(39,895)	3,987
Effect of exchange rate changes on cash	30,589	(16,572)
Net change in cash and cash equivalents	28,984	1,376
Cash and cash equivalents, beginning of period	377,223	289,469
Cash and cash equivalents, end of period	$ 406,207	$ 290,845