Consolidated Statements Of Cash Flows (USD $) In Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities:
Net earnings	$ 270,458	$ 200,195
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation of property and equipment	32,441	30,432
Loss on sale of property and equipment	183	103
Bad debt expense	6,591	6,004
Deferred income taxes	1,134	(1,978)
Stock based compensation	2,925	3,015
Amortization of non-compete agreements	445	50
Changes in operating assets and liabilities:
Trade accounts receivable	(97,533)	(93,556)
Inventories	(60,780)	(37,658)
Other current assets	(13,848)	(11,141)
Accounts payable	26,365	20,115
Accrued expenses	12,156	29,206
Income taxes	18,163	19,970
Other	(4,519)	1,536
Net cash provided by operating activities	194,181	166,293
Cash flows from investing activities:
Purchase of property and equipment	(92,479)	(42,643)
Proceeds from sale of property and equipment	2,886	3,264
Net decrease in marketable securities	5,016	831
Net decrease in other assets	301	182
Net cash used in investing activities	(84,276)	(38,366)
Cash flows from financing activities:
Proceeds from exercise of stock options	7,706	0
Tax benefits from exercise of stock options	801	0
Payment of dividends	(150,414)	(120,893)
Net cash used in financing activities	(141,907)	(120,893)
Effect of exchange rate changes on cash	(643)	679
Net (decrease) increase in cash and cash equivalents	(32,645)	7,713
Cash and cash equivalents at beginning of period	143,693	164,852
Cash and cash equivalents at end of period	111,048	172,565
Supplemental disclosure of cash flow information:
Cash paid during each period for income taxes	$ 145,358	$ 105,309