Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Operating activities
Net income	$ 68,594	$ 57,939
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation	5,559	4,470
Amortization	638	898
Share-based compensation	4,306	4,084
Excess tax benefits from share-based compensation	(1,609)	(2,021)
Equity earnings in unconsolidated investments	(171)	(162)
Other	1,248	(2,798)
Changes in operating assets and liabilities, net of effects of acquisitions:
Receivables	(157,829)	(161,549)
Product inventories	(13,289)	(40,962)
Prepaid expenses and other assets	2,612	17
Accounts payable	88,946	78,192
Accrued expenses and other current liabilities	34,516	42,953
Net cash provided by (used in) operating activities	33,521	(18,939)
Investing activities
Acquisition of businesses, net of cash acquired	(4,429)	(2,637)
Purchase of property and equipment, net of sale proceeds	(9,520)	(12,427)
Other investments, net	(166)	(113)
Net cash used in investing activities	(14,115)	(15,177)
Financing activities
Proceeds from revolving line of credit	345,631	345,049
Payments on revolving line of credit	(183,118)	(237,700)
Payments on long-term debt and other long-term liabilities	(100,012)	(125)
Payments of deferred acquisition consideration	0	(500)
Excess tax benefits from share-based compensation	1,609	2,021
Proceeds from stock issued under share-based compensation plans	7,879	7,826
Payments of cash dividends	(14,223)	(13,074)
Purchases of treasury stock	(43,866)	(43,725)
Net cash provided by financing activities	13,900	59,772
Effect of exchange rate changes on cash and cash equivalents	(482)	1,841
Change in cash and cash equivalents	32,824	27,497
Cash and cash equivalents at beginning of period	17,487	9,721
Cash and cash equivalents at end of period	$ 50,311	$ 37,218