Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities:
Net income	$ 25,971	$ 24,902
Adjustments to reconcile net income to cash flows provided by operating activities:
Depreciation and amortization	15,069	12,726
Stock-based compensation expense	3,352	2,787
Deferred taxes	26
Other non-cash items	751	(971)
Changes in assets and liabilities, net of acquisitions of businesses:
Accounts receivable, net	(24,440)	(18,780)
Inventories	(20,581)	(16,650)
Prepaid expenses and other assets	(1,996)	(2,431)
Accounts payable, accrued expenses and other liabilities	18,127	18,835
Net cash flows provided by operating activities	16,279	20,418
Cash flows from investing activities:
Capital expenditures	(17,721)	(7,706)
Acquisitions of businesses	(49,340)	(21,900)
Purchase of short-term investments		(20,985)
Proceeds from maturity of short-term investments	5,000	18,000
Other investing activities	810	1,300
Net cash flows used for investing activities	(61,251)	(31,291)
Cash flows from financing activities:
Exercise of stock options and deferred stock units	504	190
Purchase of treasury stock	(626)	(464)
Proceeds from line of credit borrowings	48,675
Repayments under line of credit	(40,600)
Other financing activities	(389)	(5)
Net cash flows provided by (used for) financing activities	7,564	(279)
Net decrease in cash	(37,408)	(11,152)
Cash and cash equivalents at beginning of period	38,880	52,365
Cash and cash equivalents at end of period	1,472	41,213
Supplemental disclosure of cash flow information:
Interest	263	239
Income taxes, net of refunds	$ 17,101	$ 18,010

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).