Stock-Based Compensation (Narrative) (Details) shares in Thousands	3 Months Ended
Mar. 31, 2018 $ / shares shares
Stock Options And SOSARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	603
Weighted-average grant date fair value \| $ / shares	$ 70.50
Stock option and SOSAR exercises (shares)	10
Shares forfeited	52
SOSARs expired	1
Granted, Weighted-Average Exercise Price \| $ / shares	$ 388.40
Stock Options And SOSARs [Member] \| Vesting Period 1 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
Stock Options And SOSARs [Member] \| Vesting Period 2 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Stock Options And SOSARs [Member] \| 3 Equal Installment Vesting [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	168
Vesting period	3 years
Stock Options And SOSARs [Member] \| 18 Month Vesting [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	175
Vesting period	18 months
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	104
Weighted-average grant date fair value \| $ / shares	$ 321.56
Restricted Stock Units [Member] \| Vesting Period 1 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
Restricted Stock Units [Member] \| Vesting Period 2 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs vested	29
Shares forfeited	24
Performance Shares [Member] \| 2018 Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance shares granted	24
Performance Shares Grant 1 [Member] \| 2018 Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value \| $ / shares	$ 323.11
Minimum [Member] \| 2018 Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price premium	110.00%
Minimum [Member] \| Performance Shares Grant 1 [Member] \| 2018 Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	0.00%
Maximum [Member] \| 2018 Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price premium	160.00%
Maximum [Member] \| Performance Shares Grant 1 [Member] \| 2018 Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	300.00%

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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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.

+ References

No definition available.

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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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

Percentage of vesting of share-based compensation awards.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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