Stock Compensation Plans (Stock Option Activity Rollforward) (Details) - Stock options [Member] - $ / shares shares in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Stock Option Activity [Roll Forward]
Outstanding, beginning of year	3,623	6,040	9,370
Granted	0	0	0
Exercised	(2,353)	(498)	(904)
Forfeited	(102)	(1,919)	(2,426)
Outstanding, end of year	1,168	3,623	6,040
Options exercisable at year end	1,168	3,623	6,040
Weighted-average per share fair value of options granted during the year	$ 0	$ 0	$ 0
Outstanding, weighted-average per share exercise price, beginning of year	12	19	23
Granted, weighted-average per share exercise price	0	0	0
Exercised, weighted-average per share exercise price	12	12	12
Forfeited, weighted-average per share exercise price	28	34	37
Options outstanding, weighted-average per share exercise price, end of year	11	12	19
Options exercisable at year end, weighted-average per share exercise price	$ 11	$ 12	$ 19

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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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