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

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

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

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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

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Note 6 - Capital Stock (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions			3 Months Ended
	Apr. 18, 2019	Jan. 23, 2019	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Apr. 20, 2017
Stock Repurchase Program, Authorized Amount						$ 500
Stock Repurchase Program, Remaining Authorized Repurchase Amount			$ 371
Treasury Stock, Shares, Acquired			0
Common Stock, Dividends, Per Share, Declared		$ 0.26	$ 0.26	$ 0.24	$ 0.24
Dividends Payable, Date to be Paid		Feb. 22, 2019
Dividends Payable, Date of Record		Feb. 08, 2019
Subsequent Event [Member]
Common Stock, Dividends, Per Share, Declared	$ 0.26
Dividends Payable, Date to be Paid	May 17, 2019
Dividends Payable, Date of Record	May 03, 2019