Share Based Compensation (Details Textuals) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Share-Based Compensation (Textuals) [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	3,821,041		3,821,041
Share based compensation available for grant full value awards subject to full value awards	1,308,576		1,308,576
Share-based compensation programs, total compensation cost	$ 1.4	$ 2.2	$ 2.8	$ 4.3
Share-based compensation cost capitalized as part of real estate assets	0.3	0.3	0.6	0.7
Total unrecognized compensation cost related to nonvested incentive awards granted	$ 7.1		$ 7.1
Total unrecognized compensation cost weighted-average period			1.6
Number of shares that were tendered to satisfy minimum statutory tax withholding requirements			2,198

The maximum number of shares available for grant subject to full value awards (which generally include equity awards other than options and stock appreciation rights) under the Company's share-based incentive compensation plan.

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- Definition

The number of vested shares that were tendered to satisfy minimum statutory tax withholding requirements related to the restricted shares that have vested in accordance with the terms of the Company's share-based incentive compensation plan.

+ Details

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- Definition

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

+ References

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
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- Definition

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

+ References

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- Definition

The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

+ References

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-Publisher FASB
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- Definition

Equity-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset.

+ References

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- Definition

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).

+ References

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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