Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Operating activities
Net income	$ 71,993	$ 57,638	$ 19,202
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	9,746	8,980	9,091
Amortization	1,559	2,348	2,454
Share-based compensation	8,233	7,790	6,429
Excess tax benefits from share-based compensation	(3,118)	(1,877)	(2,408)
Provision for doubtful accounts receivable, net of write-offs	(1,202)	(4,324)	(2,762)
Provision for inventory obsolescence, net	(11)	(721)	(24)
Change in deferred income taxes	2,605	1,795	(560)
Loss on sale of property and equipment	263	324	362
Equity (earnings) losses in unconsolidated investments	(209)	(105)	30,036
Losses (gains) on foreign currency transactions	592	(1,498)	(1,846)
Goodwill impairment	1,550	0	310
Other	195	145	115
Changes in operating assets and liabilities, net of effects of acquisitions:
Receivables	(5,887)	4,832	25,441
Product inventories	(35,339)	15,951	56,676
Prepaid expenses and other assets	(2,951)	4,694	(6,178)
Accounts payable	6,402	(14,417)	(1,815)
Accrued expenses and other current liabilities	20,682	12,404	(21,273)
Net cash provided by operating activities	75,103	93,959	113,250
Investing activities
Acquisition of businesses, net of cash acquired	(5,934)	(6,173)	(10,937)
Purchases of property and equipment, net of sale proceeds	(19,454)	(8,078)	(7,168)
Other investments	(190)	0	0
Net cash used in investing activities	(25,578)	(14,251)	(18,105)
Financing activities
Proceeds from revolving line of credit	749,349	453,039	446,937
Payments on revolving line of credit	(700,749)	(457,568)	(499,237)
Proceeds from asset-backed financing	0	0	57,000
Payments on asset-backed financing	0	0	(77,792)
Payments on long-term debt and other long-term liabilities	(149)	(48,225)	(6,157)
Payments of deferred acquisition consideration	(500)	(1,000)	0
Payments of deferred financing costs	(1,674)	(145)	(305)
Excess tax benefits from share-based compensation	3,118	1,877	2,408
Proceeds from stock issued under share-based compensation plans	13,085	6,293	4,283
Payments of cash dividends	(26,470)	(25,746)	(25,310)
Purchases of treasury stock	(76,564)	(13,683)	(1,171)
Net cash used in financing activities	(40,554)	(85,158)	(99,344)
Effect of exchange rate changes on cash and cash equivalents	(1,205)	(672)	4,280
Change in cash and cash equivalents	7,766	(6,122)	81
Cash and cash equivalents at beginning of year	9,721	15,843	15,762
Cash and cash equivalents at end of year	$ 17,487	$ 9,721	$ 15,843