Stock Incentive Plans (Narrative) (Details) (USD $) In Thousands, except Share data	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 16, 2009
Unrecognized compensation cost related to unvested restricted stock awards	$ 6,933
Common stock shares available under incentive compensation plans	2,418,983
Restricted stock awards issued	384,847	500,707
Aggregate weighted average grant date fair value, per share	$ 3,887.00	$ 3,890.00
Stock options granted	0	0
Stock options Exercised	8,389	0
Shares issued upon the exercise of stock options	8,389
Intrinsic value of outstanding and exercisable stock options	(2,800)
Maximum common shares available for purchase under warrants	1,302,083		651,042
Warrant, exercise price per share	$ 11.52
Service-Based Awards [Member]
Vesting period of service-based payment awards expensed, years	three
Unrecognized compensation cost related to unvested restricted stock awards	2,315
Performance Based Awards [Member]
Vesting period of service-based payment awards expensed, years	four
Unrecognized compensation cost related to unvested restricted stock awards	4,618
Discretionary Service Based Awards [Member]
Vesting period of service-based payment awards expensed, years	five
Restricted Stock [Member]
Share-based compensation expense related to restricted stock awards	1,780	1,418
Tax benefit related to restricted stock awards	623	496
Total fair value of awards vested	1,761	698
Unrecognized compensation cost related to unvested restricted stock awards	6,933
Accelerated vesting under incentive compensation plan's immediate vesting upon retirement provision for awards granted	$ 207
Employee Stock Option [Member]
Vesting period of service-based payment awards expensed, years	ten

Employee service share based compensation nonvested awards compensation cost not yet recognized subject to accelerated vesting.

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Represents the expense recognized during the period arising from share-based compensation arrangements (for example, shares of stock, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The exercise price of each class of warrants or rights outstanding.

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The specified number of securities that each class of warrants or rights outstanding give the holder the right but not the obligation to purchase from the issuer at a specific price, on or before a certain date.

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As of the balance-sheet date, the aggregate unrecognized cost of share-based awards made to employees under share-based compensation plans that have yet to vest.

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The total recognized tax benefit related to compensation cost for share-based payment arrangements recognized in income during the period.

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Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

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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

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The total fair value of share-based awards 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

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

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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of vested portions of options outstanding and currently exercisable under the option plan as of the balance-sheet date.

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The decrease in the number of reserved shares that could potentially be issued attributable to the exercise or conversion during the reporting period of previously issued stock options under the option plan.

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The quantity of shares issuable on stock options awarded under the plan during the reporting period.

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Number of shares issued during the period as a result of the exercise of stock options.

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