Stock-Based Compensation (ESPP - Purchase Option Activity) (Details) - 3 months ended Jun. 30, 2015 - $ / shares shares in Thousands	Total
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Exercised	(163)
Employee Stock Purchase Plan [Member] \| Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Outstanding at March 31, 2015	54
Granted	218
Exercised	(54)
Outstanding at June 30, 2015	218
Outstanding at March 31, 2015, Weighted-Average Exercise Price Per Share	$ 86.47
Granted, Weighted-Average Exercise Price Per Share	89.33
Exercised, Weighted-Average Exercise Price Per Share	89.33
Outstanding at June 30, 2015, Weighted-Average Exercise Price Per Share	$ 88.62

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Topic 718

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-Subparagraph (c)(1)(i)-(ii)

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher SEC

-Name Regulation S-X (SX)

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-Section 02

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