Consolidated Statement of Cash Flows Statement (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ 31,042us-gaap_ProfitLoss	$ 61,153us-gaap_ProfitLoss
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation	5,208us-gaap_ShareBasedCompensation	5,279us-gaap_ShareBasedCompensation
Depreciation and amortization	6,566	6,633
(Increase) decrease in value of life insurance policies	(816)	(401)
Deferred income taxes	1,996us-gaap_DeferredIncomeTaxExpenseBenefit	(2,818)us-gaap_DeferredIncomeTaxExpenseBenefit
Other non-cash items	1,499us-gaap_OtherNoncashIncomeExpense	(163)us-gaap_OtherNoncashIncomeExpense
Changes in assets and liabilities:
Accounts receivable	36,884	(7,098)
Inventories	(5,937)us-gaap_IncreaseDecreaseInInventories	(4,157)us-gaap_IncreaseDecreaseInInventories
Prepaid expenses and other current assets	8,137	(5,109)
Other assets	1,043	639
Accounts payable	1,635	915
Accrued expenses	(10,515)	3,076
Increase (Decrease) in Deferred Revenue	3,768	6,594
Other long-term liabilities	(932)	1,081
Net cash provided by operating activities	79,578	65,624
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(6,869)	(7,668)
Patents and other intangibles	(186)	0
Business acquisition, net of cash acquired	0	(1,200)
Proceeds from sale of assets	726	227
Premiums on life insurance	(647)	(1,834)
Net cash used in investing activities	(6,976)	(10,475)
CASH FLOWS FROM FINANCING ACTIVITIES:
Repayment of debt borrowings	(18,000)us-gaap_RepaymentsOfDebt	(28,011)us-gaap_RepaymentsOfDebt
Proceeds from debt borrowings	35,000us-gaap_ProceedsFromIssuanceOfDebt	40,000us-gaap_ProceedsFromIssuanceOfDebt
Excess tax benefits from stock-based compensation	(68)	329
Debt financing costs	(174)us-gaap_PaymentsOfDebtIssuanceCosts	0us-gaap_PaymentsOfDebtIssuanceCosts
Payments of Dividends	23,940us-gaap_PaymentsOfDividends	22,491us-gaap_PaymentsOfDividends
Repurchase of common shares	(69,633)	(46,811)
Net cash used in financing activities	(76,815)	(56,984)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(4,213)	(1,835)
CASH AND CASH EQUIVALENTS, beginning of period	23,350	25,088
CASH AND CASH EQUIVALENTS, end of period	$ 19,137	$ 23,253

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.