Shareholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jul. 01, 2018	Jun. 30, 2019	Jul. 01, 2018	Dec. 05, 2018
Equity [Abstract]
Stock repurchase program, number of shares authorized to be repurchased					10.0
Stock repurchased during the period (shares)			1.1	2.1
Stock repurchased during the period, value			$ 184	$ 436
Remaining number of shares authorized to be repurchased (shares)	6.4		6.4
Shares remaining to be repurchased as a percent of total shares outstanding	2.00%		2.00%
Dividends declared per share	$ 1.02	$ 0.93	$ 2.04	$ 1.86
Dividends paid in cash	$ 295	$ 276	$ 563	$ 526
Recognized net actuarial losses (pretax)			136	187
Amortization of prior service credit (pretax)			$ 11	$ 24

Stock Repurchase Program, Authorized Shares Remaining for Repurchase as a Percentage Of Total Shares Outstanding

No definition available.

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

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- Definition

Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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- Definition

Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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