Shareholders' Equity - Earnings Per Share (Details) - shares shares in Thousands	3 Months Ended
Mar. 30, 2019	Mar. 31, 2018
Weighted-average shares outstanding for basic and diluted EPS
Basic weighted-average shares outstanding	234,839	260,497
Dilutive effect of stock options	1,598	3,175
Diluted weighted-average shares outstanding	236,437	263,672
Anti-dilutive effect of weighted average shares	3,100	1,300

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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