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

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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Number of shares that have been repurchased during the period and are being held in treasury.

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

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Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended	6 Months Ended
	Jul. 16, 2018	Sep. 30, 2018	Jun. 30, 2018	Jun. 30, 2017
Subsequent Event [Line Items]
Treasury Stock, Shares, Acquired			45,540,491	34,354,967
Treasury Stock, Value, Acquired, Cost Method			$ 2,156	$ 1,810
Estimated aggregate dividend payment			$ 844	$ 868
Subsequent Event [Member]
Subsequent Event [Line Items]
Treasury Stock, Shares, Acquired		5,332,323
Treasury Stock, Value, Acquired, Cost Method		$ 236
Approved dividend, amount per share		$ 0.42
Estimated aggregate dividend payment		$ 419
Principal1035MaturityFebruary2019 [Member]
Subsequent Event [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			7.717%
Principal1035MaturityFebruary2019 [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Early Repayment of Senior Debt	$ 566
Debt Instrument, Interest Rate, Stated Percentage	7.717%