Common and preferred stock shares authorized.

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As of the balance sheet date, the number of shares related to the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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No definition available.

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As of the balance sheet date, the weighted average fair value of shares related to the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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No definition available.

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Pertains to the percentage of the lower of the market related to purchase of common stock permitted by employee stock purchase plan to be acquired by employees and employees of designated subsidiaries.

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Share based compensation by share based compensation award, options expiration period.

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Weighted average price of the stock that has been repurchased and retired during the period.

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Aggregate number of common shares reserved for future issuance.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Unrecognized cost of unvested share-based compensation awards.

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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

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No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Net number of share options (or share units) granted during the period.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

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- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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Number of shares that have been repurchased and retired during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Authorized Shares Of Common And Preferred Stock And Stock-Based Compensation Plans (Narrative) (Details) $ / shares in Units, $ in Thousands				3 Months Ended	12 Months Ended
	May 12, 2015 shares	May 14, 2013 shares	May 10, 2011 shares	Dec. 31, 2015 $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2004 shares	Dec. 31, 1997 shares	Dec. 31, 2013 shares	May 11, 2010 shares	May 10, 2005 shares	Jan. 21, 2004 shares	May 09, 1994 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional number of shares reserved for issuance		180,000,000
Common stock, shares authorized				360,000,000	360,000,000	360,000,000
Common and preferred stock shares authorized					365,000,000
Preferred stock, par value \| $ / shares				$ 0.01	$ 0.01	$ 0.01
Common stock, par value \| $ / shares				$ 0.01	$ 0.01	$ 0.01
Aggregate intrinsic value of stock options at exercise \| $					$ 0	$ 400	$ 2,500
Unrecognized stock-based compensation expense \| $					$ 0
Options granted
Preferred stock, shares authorized				5,000,000	5,000,000	5,000,000
Preferred stock, shares issued				0	0	0
Preferred stock, shares outstanding				0	0	0
Authorized common stock available for repurchase					1,134,247
Outstanding options							29,475			287,408
Weighted average exercise price, Exercisable \| $ / shares							$ 15.51
Common stock repurchased				90,913	206,780	2,591,218
Weighted average prices of common stock repurchased \| $ / shares				29.66	27.25	29.04
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense \| $					$ 93,400
Unrecognized stock-based compensation expense, shares					2,806,201
Unrecognized stock-based compensation expense, weighted average fair value \| $ / shares					$ 28.76
Weighted average period for which unrecognized stock-based compensation expense recognized					5 years 4 months 2 days
Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance											3,362,304
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional number of shares reserved for issuance			3,000,000
Percentage of the lower of the market related to purchase of common stock					85.00%
Shares of common stock reserved for future employee purchases					933,051
Shares issued during the period, in shares					1,217,829
Weighted average grant date fair value, in dollar per share \| $ / shares					$ 23.74
Employee Stock Purchase Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum employee subscription rate					15.00%
Authorized Preferred Stock And Preferred Stock Purchase Rights Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance													750,000
Incentive Plan (1994) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional number of shares reserved for issuance								1,125,000	10,631,250
Number of shares reserved for issuance														13,668,750
Expiration period from date options granted					10 years
Outstanding options				0	0	0
Incentive Plan (1994) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period, (in years)					5 years
Incentive Plan (1994) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period, (in years)					10 years
Incentive Plan (2005) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance												4,050,000
Award vesting period, (in years)					5 years
Incentive Plan (2005) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period, (in years)					3 years
Incentive Plan (2005) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period, (in years)					10 years
Incentive Plan (2010) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance					2,518,416						3,000,000
Award vesting period, (in years)					5 years
Incentive Plan (2010) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period, (in years)					3 years
Incentive Plan (2010) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period, (in years)					10 years
Incentive Plan (2015) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional number of shares reserved for issuance	3,000,000
Award vesting period, (in years)					5 years
Number of shares available for grant					4,853,654
Incentive Plan (2015) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period, (in years)					3 years
Incentive Plan (2015) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period, (in years)					10 years