Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Number of share options (or share units) exercised during the current period.

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Consolidated Statements of Stockholders' Equity (USD $) In Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Stockholders' equity, beginning balance at Dec. 31, 2011	$ 1,226,578us-gaap_StockholdersEquity	$ 1,528	$ 1,089,959	$ 3,051,447	$ (2,880,301)	$ (36,055)
Number of common shares, beginning balance at Dec. 31, 2011	152,757us-gaap_SharesIssued
Net income	461,443			461,443
Other comprehensive (loss) income	9,660					9,660
Issuance of common stock for Employee Stock Purchase Plan	4,661	1	4,660
Issuance of common stock for Employee Stock Purchase Plan, shares	66
Issuance of common stock for stock options exercised	24,208	6	24,202
Issuance of common stock for stock options exercised, shares	630
Tax benefit related to stock option plans	10,568		10,568
Increase in valuation allowance	(2,354)		(2,354)
Treasury stock	(295,878)				(295,878)
Stock-based compensation	28,471	2	28,469
Stock-based compensation, shares	243
Stockholders' equity, ending balance at Dec. 31, 2012	1,467,357us-gaap_StockholdersEquity	1,537	1,155,504	3,512,890	(3,176,179)	(26,395)
Number of common shares, ending balance at Dec. 31, 2012	153,696us-gaap_SharesIssued
Net income	450,003			450,003
Other comprehensive (loss) income	32,274					32,274
Issuance of common stock for Employee Stock Purchase Plan	4,817	1	4,816
Issuance of common stock for Employee Stock Purchase Plan, shares	58
Issuance of common stock for stock options exercised	64,141	13	64,128
Issuance of common stock for stock options exercised, shares	1,281
Tax benefit related to stock option plans	15,842		15,842
Increase in valuation allowance	(892)		(892)
Treasury stock	(301,580)				(301,580)
Stock-based compensation	31,211	1	31,210
Stock-based compensation, shares	211
Stockholders' equity, ending balance at Dec. 31, 2013	1,763,173us-gaap_StockholdersEquity	1,552	1,270,608	3,962,893	(3,477,759)	5,879
Number of common shares, ending balance at Dec. 31, 2013	155,246us-gaap_SharesIssued
Net income	431,620			431,620
Other comprehensive (loss) income	(84,584)					(84,584)
Issuance of common stock for Employee Stock Purchase Plan	5,028	1	5,027
Issuance of common stock for Employee Stock Purchase Plan, shares	54
Issuance of common stock for stock options exercised	68,821	12	68,809
Issuance of common stock for stock options exercised, shares	1,185
Tax benefit related to stock option plans	15,703		15,703
Treasury stock	(337,444)				(337,444)
Stock-based compensation	32,349	2	32,347
Stock-based compensation, shares	231
Stockholders' equity, ending balance at Dec. 31, 2014	$ 1,894,666us-gaap_StockholdersEquity	$ 1,567	$ 1,392,494	$ 4,394,513	$ (3,815,203)	$ (78,705)
Number of common shares, ending balance at Dec. 31, 2014	156,716us-gaap_SharesIssued