Share-Based Compensation Plans Share options activity (Details) (Share options [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Share options [Member]
Share Options (in shares)
Beginning outstanding	2,300	3,462
Granted	0	0
Exercised	(1,293)	(416)
Forfeited and expired	(9)	(2)
Outstanding at end of period	998	3,044
Exercisable at end of period	998	2,928
Weighted-Average Exercise Price (in dollars per share)
Beginning outstanding	$ 32	$ 32
Granted	$ 0	$ 0
Exercised	$ 26	$ 33
Forfeited and expired	$ 36	$ 36
Outstanding at end of period	$ 39	$ 32
Exercisable at end of period	$ 39	$ 32

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=6415400&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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Weighted average price of options that were either forfeited or expired.

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-SubTopic 10

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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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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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