Compensation Plans (Tables)	12 Months Ended
Dec. 31, 2011
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of performance share awards under equity incentive compensation plan	e
Schedule of restricted stock unit incentive program under equity incentive compensation plan	e
Schedule of stock option grants under prior stock option plans	a
Schedule of Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding [Table Text Block]	l
Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]	t
Schedule of Net Profits Plan Cash Payment Allocation [Table Text Block] [Table Text Block]	b

Schedule of Net Profits Plan Cash Payment Allocation [Table Text Block]

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- Definition

Tabular disclosure of the number and weighted-average grant date fair value for performance share awards that were outstanding at the beginning and end of the period, and the number of performance share units that were granted, vested, or forfeited during the period.

+ References

No definition available.

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Tabular disclosure of of the following for fully vested share options (or share units) and share options expected to vest at the date of the latest statement of financial position: the number, weighted-average exercise price (or conversion ratio), aggregate intrinsic value (except for nonpublic entities), and weighted-average remaining contractual term of options (or share units) outstanding.

+ References

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

-Topic 718

-SubTopic 10

-Publisher FASB

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-Article

-Subparagraph (e)(1)

-Name Accounting Standards Codification

-Paragraph 2

-Section 50

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Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year.

+ References

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

-Topic 718

-SubTopic 10

-Publisher FASB

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-Subparagraph (c)(1)

-Name Accounting Standards Codification

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-Section 50

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Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year.

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Tabular disclosure of the significant assumptions used during the year to estimate the fair value of employee stock purchase plans, including, but not limited to: (a) expected term, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions.

+ References

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

-Topic 718

-SubTopic 10

-Publisher FASB

-Number

-Article

-Subparagraph (f)(2)

-Name Accounting Standards Codification

-Paragraph 2

-Section 50

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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