Statement of Cash Flows (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 243,194,000	$ 216,612,000	$ 184,644,000
Adjustments to reconcile income to net cash provided by operating activities:
Share-based Compensation	20,526,000	18,381,000	17,165,000
Depreciation and amortization	25,471,000	22,917,000	23,303,000
Debt issuance costs amortization and finance charges	480,000	479,000	5,956,000
Loss on exchange of Senior Exchangeable Notes	0	0	1,012,000
(Increase) decrease in value of life insurance policies	(5,112,000)	(1,636,000)	285,000
Deferred Income Tax Expense (Benefit)	6,790,000	3,605,000	(6,549,000)
Other Noncash Income (Expense)	237,000	263,000	346,000
Changes in assets and liabilities, net of effects of acquisitions:
Accounts receivable	(16,312,000)	(16,664,000)	(12,082,000)
Inventories	1,291,000	3,224,000	(16,033,000)
Prepaid expenses and other current assets	13,915,000	(12,904,000)	(1,228,000)
Other assets	(867,000)	426,000	680,000
Accounts payable	(6,339,000)	(3,672,000)	11,969,000
Accrued expenses	2,998,000	4,871,000	(13,754,000)
Other long-term liabilities	11,865,000	1,300,000	9,424,000
Net cash provided by operating activities	298,137,000	237,202,000	204,126,000
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(35,416,000)	(31,151,000)	(29,927,000)
Patents and other intangibles	(3,530,000)	(1,648,000)	(220,000)
Acquisitions, net of cash acquired	0	(556,000)	(18,821,000)
Cash in escrow	0	2,188,000	(2,179,000)
Payments for (Proceeds from) Investments	(98,000)	(322,000)	0
Proceeds from sale of assets	1,036,000	667,000	900,000
Proceeds from insurance recovery	1,385,000	101,000	1,300,000
Premiums on life insurance	(6,575,000)	(3,283,000)	(3,071,000)
Net cash used in investing activities	(43,198,000)	(34,004,000)	(52,018,000)
CASH FLOWS FROM FINANCING ACTIVITIES:
Repayment of debt borrowings	(134,046,000)	(112,346,000)	(348,564,000)
Proceeds from debt borrowings	167,000,000	121,000,000	417,426,000
Stock options exercised	83,000	5,000	297,000
Excess tax benefits from stock-based payments	3,744,000	5,226,000	2,559,000
Debt financing costs	0	(7,000)	(2,014,000)
Settlement of Warrants	0	0	219,451,000
Non-controlling interest - contributions	0	1,800,000	1,194,000
Non-controlling interest - dividend	0	(300,000)	(251,000)
Dividends paid	(58,642,000)	(52,950,000)	(46,027,000)
Repurchase of common shares	(227,216,000)	(175,732,000)	(61,825,000)
Net cash used in financing activities	(249,077,000)	(213,304,000)	(256,656,000)
NET CHANGE IN CASH AND CASH EQUIVALENTS	5,862,000	(10,106,000)	(104,548,000)
Cash and Cash Equivalents, at Carrying Value	25,088,000	19,226,000	29,332,000
Cash payments for interest	8,869,000	7,352,000	2,308,000
Cash payments for income taxes	57,001,000	85,660,000	74,724,000
Financed capital expenditures	$ 5,797,000	$ 3,910,000	$ 1,273,000