Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Operating Activities:
Net earnings	$ 107,332	$ 84,195
Adjustments to reconcile net earnings to net cash from operating activities:
Provision for losses (recoveries) on accounts receivable	277	(1,115)
Deferred income tax expense	11,937	7,194
Excess tax benefits from stock plans	(1,480)	(489)
Stock compensation expense	9,907	10,294
Depreciation and amortization	11,529	12,382
Other	86	138
Changes in operating assets and liabilities:
(Increase) decrease in accounts receivable	(46,790)	12,228
Increase in accounts payable and accrued expenses	14,895	29,546
Increase in income taxes payable, net	23,132	18,205
Decrease in other current assets	3,569	1,279
Net cash from operating activities	134,394	173,857
Investing Activities:
Purchase of short-term investments	(22)	(81,130)
Proceeds from maturities of short-term investments	40,296	20,976
Purchase of property and equipment	(9,445)	(8,760)
Other, net	198	1,670
Net cash from investing activities	31,027	(67,244)
Financing Activities:
Proceeds from issuance of common stock	35,048	7,892
Repurchases of common stock	(77,368)	(226,725)
Excess tax benefits from stock plans	1,480	489
Distributions to noncontrolling interest	(857)	(85)
Net cash from financing activities	(41,697)	(218,429)
Effect of exchange rate changes on cash and cash equivalents	(17,687)	(4,790)
Increase (decrease) in cash and cash equivalents	106,037	(116,606)
Cash and cash equivalents at beginning of period	927,107	1,247,652
Cash and cash equivalents at end of period	1,033,144	1,131,046
Taxes Paid:
Income taxes	$ 28,261	$ 27,496