Stock Incentive Plans (Details 1)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Summary of stock options activity
Option exercises, Shares	498,549,000	213,724	341,371

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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