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Amount of stock repurchase plan authorized.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the par value method.

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Stockholders' Equity - Narrative (Details) $ / shares in Units, shares in Millions	1 Months Ended	3 Months Ended
	Jul. 31, 2019 $ / shares	Jun. 30, 2019 USD ($) vote $ / shares shares	Jun. 30, 2018 $ / shares	May 31, 2019 USD ($)
Accelerated Share Repurchases [Line Items]
Number of votes per share of common stock permitted on proposals presented to stockholders (vote) \| vote		1
Dividends declared per common share (in dollars per share)		$ 0.39	$ 0.34
Accelerated Share Repurchase
Accelerated Share Repurchases [Line Items]
Authorized repurchase amount (up to) \| $				$ 600,000,000
Common stock repurchased (shares) \| shares		4.7
Average price per share of shares repurchased (in usd per share)		$ 127.68
Authorized amount available for future repurchases \| $		$ 2,800,000,000
Open Market Transactions
Accelerated Share Repurchases [Line Items]
Common stock repurchased (shares) \| shares		0.7
Value of shares repurchased under the ASR program \| $		$ 84,000,000
Average price per share of shares repurchased (in usd per share)		$ 128.64
Subsequent Event
Accelerated Share Repurchases [Line Items]
Dividends declared per common share (in dollars per share)	$ 0.41