Common Stock, Stock Option Plans and Stock Compensation Agreements - Narrative (Details) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($) StockBasedCompensationPlans $ / shares shares	Jan. 01, 2017 USD ($) $ / shares shares	Jan. 03, 2016 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock-based compensation plans \| StockBasedCompensationPlans	2
Compensation cost charged for Long term incentive plan	$ 962.0	$ 878.0	$ 874.0
Total income tax benefit recognized	275.0	256.0	253.0
Excess tax benefits		353.0
Total compensation cost not yet recognized for option	$ 798.0	$ 749.0	$ 744.0
Weighted average period for total compensation cost not yet recognized	1 year 9 months 4 days	1 year 1 month 2 days	11 months 23 days
Average fair value of option granted (in dollars per share) \| $ / shares	$ 13.38	$ 10.01	$ 10.68
Total intrinsic value of options exercised	$ 1,060.0	$ 980.0	$ 644.0
Stock options outstanding (in shares) \| shares	111,306	113,455	116,517
Stock option average life	6 years 3 months 18 days	6 years 2 months 12 days	5 years 10 months 24 days
Stock options exercisable \| shares		50,414	48,345
Stock options average price \| $ / shares		$ 65.77	$ 62.26
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options expiration period	10 years
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average fair value of RSU's and PSU's granted \| $ / shares	$ 107.69	$ 92.45	$ 91.65
Fair Value of RSU or PSU units settled	$ 596.5	$ 587.7	$ 597.6
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Average fair value of RSU's and PSU's granted \| $ / shares	$ 114.13	$ 105.30	$ 93.54
Fair Value of RSU or PSU units settled	$ 132.5	$ 127.7	$ 16.7
Minimum \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	6 months
Minimum \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	6 months
Minimum \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	6 months
Vesting percentage	0.00%
Maximum \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Maximum \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Maximum \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Vesting percentage	200.00%
2012 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance under long-term incentive plan \| shares	650,000
Shares available for future grants under long-term incentive plan \| shares	389,000

Effective Income Tax Rate Reconciliation Share-based Compensation Excess Tax Benefit Amount

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Number of stock-based compensation plans.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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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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The weighted average fair value at grant date for nonvested equity-based awards issued 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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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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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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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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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Percentage of vesting of share-based compensation awards.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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