The additional amount of stock repurchase plan authorized.

No definition available.

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- Definition

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

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

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

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- Definition

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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Note 6 - Capital Stock (Details Textual) - USD ($) $ / shares in Units, $ in Millions				3 Months Ended		6 Months Ended
	Jul. 19, 2018	Apr. 19, 2018	Apr. 20, 2017	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Oct. 22, 2015
Stock Repurchase Program, Authorized Amount								$ 500
Stock Repurchase Program, Additional Authorized Amount			$ 500
Stock Repurchase Program, Remaining Authorized Repurchase Amount				$ 471		$ 471
Treasury Stock, Shares, Acquired						420,000
Treasury Stock, Value, Acquired, Cost Method						$ 50
Common Stock, Dividends, Per Share, Declared		$ 0.24		$ 0.24	$ 0.23	$ 0.48	$ 0.46
Dividends Payable, Date to be Paid		May 18, 2018
Dividends Payable, Date of Record		May 04, 2018
Subsequent Event [Member]
Common Stock, Dividends, Per Share, Declared	$ 0.24
Dividends Payable, Date to be Paid	Aug. 17, 2018
Dividends Payable, Date of Record	Aug. 03, 2018