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Equity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Equity [Abstract]
Stock repurchased (in shares)					7.8
Common stock issued under stock compensation plan (in shares)					3.3
Net decrease in period (in shares)					4.5
Increase in quarterly dividend rate (in dollars per share)		$ 0.005
Dividends declared (in dollars per share)	$ 0.115	$ 0.115	$ 0.110	$ 0.110	$ 0.230	$ 0.220
Dividends declared	$ 29.3

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- Definition

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

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Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

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Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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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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