Derivative and Other Fair Value Instruments (Details 5) (USD $) In Thousands	Dec. 31, 2010	Dec. 31, 2009
Assets
Derivatives	$ 15,797	$ 28,816
Supplemental Executive Retirement Plan	58,132	61,090
Available-for-Sale Investment Securities	1,194	26,138
Total	75,123	116,044
Liabilities
Derivatives	39,078	3,577
Supplemental Executive Retirement Plan	58,132	61,090
Total	97,210	64,667
Redeemable Noncontrolling Interests - Operating Partnership	383,540	258,280
Quoted Priced in Active Markets for Identical Assets (Level 1) [Member]
Assets
Derivatives	0	0
Supplemental Executive Retirement Plan	58,132	61,090
Available-for-Sale Investment Securities	1,194	1,045
Total	59,326	62,135
Quoted Priced in Active Markets for Identical Assets (Level 1) [Member]
Liabilities
Derivatives	0	0
Supplemental Executive Retirement Plan	58,132	61,090
Total	58,132	61,090
Redeemable Noncontrolling Interests - Operating Partnership	0	0
Significant Other Observable Inputs (Level 2) [Member]
Assets
Derivatives	15,797	28,816
Supplemental Executive Retirement Plan	0	0
Available-for-Sale Investment Securities	0	25,093
Total	15,797	53,909
Significant Other Observable Inputs (Level 2) [Member]
Liabilities
Derivatives	39,078	3,577
Supplemental Executive Retirement Plan	0	0
Total	39,078	3,577
Redeemable Noncontrolling Interests - Operating Partnership	383,540	258,280
Significant Unobservable Inputs (Level 3) [Member]
Assets
Derivatives	0	0
Supplemental Executive Retirement Plan	0	0
Available-for-Sale Investment Securities	0	0
Total	0	0
Significant Unobservable Inputs (Level 3) [Member]
Liabilities
Derivatives	0	0
Supplemental Executive Retirement Plan	0	0
Total	0	0
Redeemable Noncontrolling Interests - Operating Partnership	$ 0	$ 0

Total fair-value assets measured on recurring basis.

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Fair value assets measured on recurring basis.

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Total fair-value liabilities measured on recurring basis.

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Fair value liabilities measured on recurring basis.

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Fair value of employee holdings other than common shares within the supplemental executive retirement plan at the balance sheet date.

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Fair Value of Company's obligation to employees related to employee holdings other than common shares within the Supplemental Executive Retirement Plan at the balance sheet date.

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- Definition

The greater of carrying value (book value) or fair market value of an entity's issued and outstanding stock which is not included within permanent equity in Stockholders Equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity.

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This item represents the total of all debt securities grouped by maturity dates, at fair value, which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 20

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Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 205G

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph a

-Clause 1

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Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

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+ Details

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