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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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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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- Definition

Face amount or stated value per share of common stock.

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- Definition

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

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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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- Definition

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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- Definition

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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- Definition

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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- Definition

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.

+ References

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.

+ References

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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- Definition

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 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.

+ References

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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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Authorized Shares Of Common And Preferred Stock And Stock-Based Compensation Plans (Narrative) (Details)			6 Months Ended	12 Months Ended
	May. 14, 2013 shares	May. 10, 2011 shares	Jun. 30, 2015 $ / shares shares	Dec. 31, 2004 shares	Dec. 31, 1997 shares	May. 12, 2015 shares	Dec. 31, 2014 $ / shares 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
Number of shares reserved for issuance								3,362,304
Common and preferred stock shares authorized			365,000,000
Preferred stock, par value \| $ / shares			$ 0.01				$ 0.01
Common stock, par value \| $ / shares			$ 0.01				$ 0.01
Preferred stock, shares authorized			5,000,000				5,000,000
Preferred stock, shares issued			0
Preferred stock, shares outstanding			0
Authorized common stock available for repurchase			3,644,241
Outstanding options			0
Common stock repurchased			288,004
Weighted average prices of common stock repurchased \| $ / shares			29.67
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			2,697,481
Shares issued during the period, in shares			561,552
Weighted average grant date fair value, in dollar per share \| $ / shares			$ 24.93
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
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] \| Restricted Stock Plan [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] \| Restricted Stock Plan [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] \| Restricted Stock Plan [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
Incentive Plan (2010) [Member] \| Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance								3,000,000
Award vesting period, (in years)			5 years
Incentive Plan (2010) [Member] \| Restricted Stock Plan [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] \| Restricted Stock Plan [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]
Number of shares reserved for issuance						3,000,000
Number of shares available for grant			5,555,523
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] \| Midpoint [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period, (in years)			5 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