This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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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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- Definition

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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- Definition

Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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- Definition

Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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- Definition

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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- Definition

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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- Definition

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

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Value of stock issued as a result of the exercise of stock options.

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Common stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury stock	Total
Balance at Dec. 31, 2011	$ 994	$ 229,301	$ 1,168,644	$ (1,547)	$ (418,234)	$ 979,158us-gaap_StockholdersEquity
Balance (in shares) at Dec. 31, 2011	198,729,000				(24,452,000)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation		28,007				28,007
Exercise of stock options	25	10,989				11,014
Exercise of stock options (in shares)	5,030,000
Excess tax benefits from share based payment arrangements		19,656				19,656
Repurchase of common stock					(737,079)	(737,079)
Repurchase of common stock (in shares)					(13,531,000)
Foreign currency translation				2,096		2,096
Reclassification adjustment for net gains included in net income				1,525		1,525
Net income			340,020			340,020
Balance at Dec. 31, 2012	1,019	287,953	1,508,664	2,074	(1,155,313)	644,397us-gaap_StockholdersEquity
Balance (in shares) at Dec. 31, 2012	203,759,000				(37,983,000)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation		28,528				28,528
Exercise of stock options	11	21,240				21,251
Exercise of stock options (in shares)	2,255,000
Excess tax benefits from share based payment arrangements		30,348				30,348
Repurchase of common stock					(67,599)	(67,599)
Repurchase of common stock (in shares)					(1,209,000)
Foreign currency translation				(1,782)		(1,782)
Reclassification adjustment for net gains included in net income				(1,525)		(1,525)
Net income			338,661			338,661
Balance at Dec. 31, 2013	1,030	368,069	1,847,325	(1,233)	(1,222,912)	992,279us-gaap_StockholdersEquity
Balance (in shares) at Dec. 31, 2013	206,014,000				(39,192,000)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation		28,989				28,989
Exercise of stock options	5	17,163				17,168
Exercise of stock options (in shares)	990,000
Excess tax benefits from share based payment arrangements		11,924				11,924
Repurchase of common stock					(8,175)	(8,175)
Repurchase of common stock (in shares)					(90,000)
Foreign currency translation				(10,220)		(10,220)
Net income			483,185			483,185
Balance at Dec. 31, 2014	$ 1,035	$ 426,145	$ 2,330,510	$ (11,453)	$ (1,231,087)	$ 1,515,150us-gaap_StockholdersEquity
Balance (in shares) at Dec. 31, 2014	207,004,000				(39,282,000)