Employee Incentive Plans, Textuals (Details) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2011 years mmlbs basispoints	Sep. 30, 2010
Employee Incentive Plans (Details Textual) [Abstract]
Number of common shares authorized for issuance under Equity Incentive Plan	2,722,222
Number of common shares available for additional awards under Equity Incentive Plan	827,169
Number of common share received by the employee on vesting of restricted stock unit	1
Stock options expired	1,286
Fully-vested options outstanding	20,791
Exercise price of options to purchase common stock	$ 80.01
Remaining contractual life of options outstanding	5.5
Weighted average grant date fair value of options outstanding	$ 39.90
Stock options granted	0
Stock options forfeited	0
Stock options exercised	0
Share-based compensation expense relating to common shares granted to non-employee directors in lieu of annual retainer	$ 0.2	$ 0.2
Common shares withheld and cancelled	23,445	9,984
French Subsidiary [Member] \| Restricted Stock Units (RSUs) [Member] \| Second anniversary of the grant date
Employee Incentive Plans (Details Textual) [Abstract]
Share based award vesting schedule	0.67
French Subsidiary [Member] \| Restricted Stock Units (RSUs) [Member] \| Third anniversary of the grant date
Employee Incentive Plans (Details Textual) [Abstract]
Share based award vesting schedule	0.33
Non-French Subsidiary [Member] \| Restricted Stock Units (RSUs) [Member]
Employee Incentive Plans (Details Textual) [Abstract]
Award requisite service period	3 years
Non-French Subsidiary [Member] \| Restricted Stock Units (RSUs) [Member] \| First anniversary of the grant date
Employee Incentive Plans (Details Textual) [Abstract]
Share based award vesting schedule	0.33
Non-French Subsidiary [Member] \| Restricted Stock Units (RSUs) [Member] \| Second anniversary of the grant date
Employee Incentive Plans (Details Textual) [Abstract]
Share based award vesting schedule	0.33
Non-French Subsidiary [Member] \| Restricted Stock Units (RSUs) [Member] \| Third anniversary of the grant date
Employee Incentive Plans (Details Textual) [Abstract]
Share based award vesting schedule	0.33
Non-Vested Common Shares [Member] \| Non Employee Directors [Member]
Employee Incentive Plans (Details Textual) [Abstract]
Award requisite service period	1 year
Non-Vested Common Shares [Member] \| Executive Officers and Senior Management [Member]
Employee Incentive Plans (Details Textual) [Abstract]
Award requisite service period	3 years
Non-Vested Common Shares [Member] \| Other key Employees [Member]
Employee Incentive Plans (Details Textual) [Abstract]
Award requisite service period	3 years
Performance Shares [Member]
Employee Incentive Plans (Details Textual) [Abstract]
Award requisite service period	3 years

Common shares withheld and cancelled to satisfy statutory tax withholding obligation.

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Employee Incentive Plans.

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Number of common share received by the employee on vesting of restricted stock unit.

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Noninterest expense related to directors' fees which are fees paid by an Entity to its directors. Directors' fees may be paid in addition to salary and other benefits.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 225

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Description of the estimated period of time over which an employee is required to provide service in exchange for the equity-based payment award, which often is the vesting period. This period may be explicit or implicit based on the terms of the award, and may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

+ References

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Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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The weighted average period between the balance sheet date and expiration for all vested portions of options outstanding and currently exercisable (or convertible) under the plan, which may be expressed in a decimal value for number of years.

+ References

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The decrease in the number of shares that could be issued attributable to the lapse of rights to exercise previously issued stock options under the terms of the option agreements under the plan during the reporting period.

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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.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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

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