Stock Option Plan (Narrative) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Stock options granted
Stock options vested	0	0
Aggregate intrinsic value of the outstanding stock options	$ 0
Stock option exercised		0
Weighted average contractual remaining term of stock option outstanding, years	1.44
Common shares outstanding	75,545	82,700	78,075
Treasury shares available	752,129		752,128
2005 Stock Compensation Plan [Member]
Treasury shares available	488,761

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Net number of share options (or share units) granted during the period.

+ References

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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to options outstanding under the plan as of the balance sheet date.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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

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

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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