Stock Compensation - Exercise Price Range (Details) - Employee Stock Option - Long-term incentive and director compensation plans - $ / shares	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Minimum	$ 14.47
Exercise Price Range, Maximum	$ 113.30
Number Outstanding (Shares)	39,905,454	44,754,593
Weighted Average Remaining Contractual Life (Years)	5 years 10 months 24 days
Options Outstanding Weighted Average Exercise Price per Share	$ 56.10	$ 48.49
Number Exercisable (Shares)	23,625,802
Options Exercisable Weighted Average Exercise Price per Share	$ 42.76
Range Of Exercise Prices $14.47 to $20.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Minimum	14.47
Exercise Price Range, Maximum	$ 20.00
Number Outstanding (Shares)	573,629
Weighted Average Remaining Contractual Life (Years)	1 month 6 days
Options Outstanding Weighted Average Exercise Price per Share	$ 14.96
Number Exercisable (Shares)	573,629
Options Exercisable Weighted Average Exercise Price per Share	$ 14.96
Range Of Exercise Prices $20.01 to $40.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Minimum	20.01
Exercise Price Range, Maximum	$ 40.00
Number Outstanding (Shares)	9,508,056
Weighted Average Remaining Contractual Life (Years)	2 years 10 months 24 days
Options Outstanding Weighted Average Exercise Price per Share	$ 31.21
Number Exercisable (Shares)	9,508,056
Options Exercisable Weighted Average Exercise Price per Share	$ 31.21
Range Of Exercise Prices $40.01 to $60.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Minimum	40.01
Exercise Price Range, Maximum	$ 60.00
Number Outstanding (Shares)	19,883,804
Weighted Average Remaining Contractual Life (Years)	6 years 2 months 12 days
Options Outstanding Weighted Average Exercise Price per Share	$ 50.95
Number Exercisable (Shares)	12,397,285
Options Exercisable Weighted Average Exercise Price per Share	$ 49.53
Range Of Exercise Prices $60.01 to $80.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Minimum	60.01
Exercise Price Range, Maximum	$ 80.00
Number Outstanding (Shares)	5,612,386
Weighted Average Remaining Contractual Life (Years)	8 years 1 month 6 days
Options Outstanding Weighted Average Exercise Price per Share	$ 79.21
Number Exercisable (Shares)	1,143,118
Options Exercisable Weighted Average Exercise Price per Share	$ 79.20
Range Of Exercise Prices $80.01 to $100.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Minimum	80.01
Exercise Price Range, Maximum	$ 100.00
Number Outstanding (Shares)	37,917
Weighted Average Remaining Contractual Life (Years)	9 years 3 months 18 days
Options Outstanding Weighted Average Exercise Price per Share	$ 91.16
Number Exercisable (Shares)	3,714
Options Exercisable Weighted Average Exercise Price per Share	$ 91.54
Range Of Exercise Prices $100.01 to $113.30
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Minimum	100.01
Exercise Price Range, Maximum	$ 113.30
Number Outstanding (Shares)	4,289,662
Weighted Average Remaining Contractual Life (Years)	9 years 1 month 6 days
Options Outstanding Weighted Average Exercise Price per Share	$ 110.15
Number Exercisable (Shares)	0
Options Exercisable Weighted Average Exercise Price per Share	$ 0

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

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

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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