Stock Incentive Plans (Summary Of Information Concerning Restricted Stock Awards) (Details) (USD $)	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Stock Incentive Plans [Abstract]
Awards, Unvested awards outstanding at beginning of period	1,309,489	854,440
Awards, Granted	384,847	500,707
Awards, Net performance adjustment	150,889
Awards, Vested	(172,030)	(95,281)
Awards, Forfeited	(1,397)	(32,008)
Awards, Dividend reinvestment	52,656	50,208
Awards, Unvested awards outstanding at end of period	1,724,454	1,278,066
Weighted Average Grant Price, Unvested awards outstanding at beginning of period	$ 8.52	$ 10.57
Weighted Average Grant Price, Granted	$ 10.10	$ 7.77
Weighted Average Grant Price, Net performance adjustment	$ 7.92
Weighted Average Grant Price, Vested	$ 13.57	$ 15.05
Weighted Average Grant Price, Forfeited	$ 9.20	$ 9.21
Weighted Average Grant Price, Dividend reinvestment	$ 9.69	$ 8.37
Weighted Average Grant Price, Unvested awards outstanding at end of period	$ 8.36	$ 9.09

Share based compensation arrangement by share based payment award equity instruments other than options dividend reinvestment.

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Share based compensation arrangement by share based payment award equity instruments other than options dividend reinvestment in period weighted average grant date fair value.

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Share-based compensation arrangement by share-based payment award, equity instruments other than options, net performance adjustment.

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Share-based compensation arrangement by share-based payment award, equity instruments other than options, weighted average net performance adjustment fair value.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The weighted average fair value as of the grant date of equity-based award plans other than stock (unit) 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.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit 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 or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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

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