Stock Compensation Plans (Stock Option Activity Rollforward) (Details) - Stock options [Member] - $ / shares shares in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock Option Activity [Roll Forward]
Outstanding, beginning of year	563	1,168	3,623
Granted	0	0	0
Exercised	(547)	(605)	(2,353)
Forfeited	0	0	(102)
Outstanding, end of year	16	563	1,168
Options exercisable at year end	16	563	1,168
Outstanding, weighted-average per share exercise price, beginning of year	$ 12	$ 11	$ 12
Granted, weighted-average per share exercise price	0	0	0
Exercised, weighted-average per share exercise price	12	11	12
Forfeited, weighted-average per share exercise price	0	0	28
Options outstanding, weighted-average per share exercise price, end of year	8	12	11
Options exercisable at year end, weighted-average per share exercise price	$ 8	$ 12	$ 11

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Net number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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