Stock-Based Compensation (Narrative) (Details) shares in Thousands	3 Months Ended
Mar. 31, 2019 $ / shares item shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of types of PSU awards \| item	2
Stock Options And SOSARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	179
Weighted-average grant date fair value \| $ / shares	$ 172.28
Granted, Weighted-Average Exercise Price \| $ / shares	$ 584.90
Units forfeited	15
Units expired	45
Stock option exercises (shares)	412
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
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	21
Weighted-average grant date fair value \| $ / shares	$ 585.62
Units forfeited	6
Units released	42
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]
Performance shares granted	46
Weighted-average grant date fair value \| $ / shares	$ 582.77
Units forfeited	12
Performance Shares Grant 1 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance shares granted	33
Vesting period	3 years
Performance Shares Grant 2 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance shares granted	13
Performance Shares Grant 2 [Member] \| Vesting Period 1 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	40.00%
Performance Shares Grant 2 [Member] \| Vesting Period 2 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	60.00%
Minimum [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	0.00%
Maximum [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	300.00%

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Releases in Period

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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).

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

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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.

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

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

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Percentage of vesting of award under share-based payment arrangement.

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

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