Stock Compensation Plans (Details 3) (Stock Awards Plan [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008	Dec. 31, 2007
Stock Awards Plan [Member]
Stock Award Activity (Table Amounts)
Stock awards - outstanding at January 1	3,658	3,276	5,144
Stock awards - granted	2,317	2,356	1,505
Stock awards - vested	(1,319)	(1,645)	(2,950)
Stock awards - forfeited	(356)	(329)	(423)
Stock awards - outstanding at December 31	4,300	3,658	3,276	5,144
Stock awards - available for grant at December 31, 2010	2,110
Weighted-average grant date fair value - outstanding at January 1	$ 58	$ 75	$ 67
Weighted-average grant date fair value - granted	$ 60	$ 45	$ 80
Weighted-average grant date fair value - vested	$ 79	$ 71	$ 64
Weighted-average grant date fair value - forfeited	$ 56	$ 66	$ 65
Weighted-average grant date fair value - outstanding at December 31	$ 53	$ 58	$ 75	$ 67
Weighted-average remaining contractual term - outstanding at January 1 (years)	1.5	1.6	1.4	1.3
Weighted-average remaining contractual term - outstanding at December 31 (years)	1.5	1.6	1.4	1.3

The weighted average period between the balance-sheet date and vesting of stock awards outstanding under the plan, which may be expressed in a decimal value for number of years.

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- Definition

The difference between the maximum number of shares authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares already issuable for which the grantee has gained the right during the reporting period, by satisfying service and performance requirements, to receive certain shares or retain shares, other instruments, or cash in accordance with the terms of the arrangement , and 2) shares reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

The number of shares under a share-based award plan other than a stock option plan that were settled during the reporting period due to a failure to satisfy vesting conditions pertaining to all option plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(e)

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- Definition

The weighted average fair value as of the grant date of share-based award plans other than stock option plans that were not exercised or put into effect during the reporting period as a result of the occurrence of a terminating event specified in the contractual agreement of the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(e)

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- Definition

The number of shares issuable under a share-based award plan pertaining to grants made during the period on other than stock option plans (for example, phantom stock plan, stock appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(c)

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- Definition

The weighted average fair value at grant for nonvested share-based awards issued during the period on other than stock option plans (for example, phantom stock plan, stock appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(c)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph c(1)

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- Definition

The number of outstanding awards on nonstock option plans (for example, phantom stock plan, stock appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(a)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(b)

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- Definition

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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- Definition

The weighted average fair value of nonvested awards on share-based plans excluding option plans (for example, phantom stock plan, stock appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(a)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(b)

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- Definition

The decrease in the number of shares potentially issuable under a share-based award plan pertaining to awards for which the grantee has gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares, other instruments, or cash in accordance with the terms of the arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(d)

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- Definition

The weighted average fair value as of grant dates pertaining to a share-based award plan other than a stock option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares, other instruments, or cash in accordance with the terms of the arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(d)

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