Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities:
Net income	$ 137,742	$ 111,722	$ 51,573
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	11,725	10,771	8,533
Share-based compensation	6,663	5,175	5,264
Deferred income tax provision	8,310	12,725	1,972
Provision for doubtful accounts	2,374	3,016	5,934
Non-cash contribution for 401(k) plan	1,718	489	1,297
Loss (gain) on sale of property and equipment	171	(432)	(47)
Excess tax benefits from share-based compensation	(859)	(2,862)	(9,589)
Changes in operating assets and liabilities, net of effects of acquisitions:
Accounts receivable	11,987	(41,250)	67,243
Inventories	(22,489)	21,447	1,204
Accounts payable and other liabilities	(98,611)	28,088	(46,386)
Other, net	2,721	3,910	1,289
Net cash provided by operating activities	61,452	152,799	88,287
Cash flows from investing activities:
Business acquisitions, net of cash acquired	(43,455)	(3,824)	(9,840)
Capital expenditures	(13,925)	(8,421)	(5,912)
Proceeds from sale of property and equipment	737	2,111	249
Net cash used in investing activities	(56,643)	(10,134)	(15,503)
Cash flows from financing activities:
Dividends on Common and Class B common stock	(73,276)	(66,028)	(57,085)
Distributions to noncontrolling interest	(26,469)	(13,644)	(4,808)
Return of capital contribution to noncontrolling interest	(32,000)
Repayments of other long-term obligations	(69)	(729)	(234)
Payment of fees related to revolving credit agreements	(38)		(6,695)
Excess tax benefits from share-based compensation	859	2,862	9,589
Net proceeds from issuances of common stock	5,359	6,042	10,335
Net borrowings (repayments) under revolving credit agreements	10,000	(2,763)	(7,237)
Net cash used in financing activities	(115,634)	(74,260)	(56,135)
Net (decrease) increase in cash and cash equivalents	(110,825)	68,405	16,649
Cash and cash equivalents at beginning of year	126,498	58,093	41,444
Cash and cash equivalents at end of year	$ 15,673	$ 126,498	$ 58,093

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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).