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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Equity - Summary of Dividends Paid and Stock Repurchases and Retirements (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions					3 Months Ended				6 Months Ended	9 Months Ended
	Sep. 25, 2019	Jun. 24, 2019	Apr. 29, 2019	Mar. 22, 2019	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2018
Dividends
Per share (in dollars per share)	$ 0.19	$ 0.19		$ 0.19	$ 0.19		$ 0.18			$ 0.57	$ 0.54
Amount					$ 64.7		$ 62.1			$ 196.4	$ 187.0
Repurchased under the 2018 Stock Repurchase Program
Amount					$ 111.1		$ 151.3			$ 354.9	$ 755.5
Stock Repurchase Program 2018
Repurchased under the 2018 Stock Repurchase Program
Shares (in shares)					5.1		6.0			13.7	29.3
Average price per share (in dollars per share)					$ 24.90		$ 25.62			$ 25.45	$ 25.62
Amount					$ 50.0		$ 0.0			$ 350.0	$ 750.0
Accelerated Share Repurchase Program
Repurchased under the 2018 Stock Repurchase Program
Shares (in shares)						8.6				29.3
Average price per share (in dollars per share)			$ 27.94						$ 25.79	$ 25.62
Amount								$ 240.0