Basis Of Presentation And Summary Of Significant Accounting Policies (Carrying Value Of note receivable, Indebtedness And Corresponding Estimate Of Fair Value) (Details) $ in Thousands	6 Months Ended
Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Document Period End Date	Jun. 30, 2019
Related party note receivable	$ 80,000	$ 80,000
Note receivable	19,718	19,468
Mortgage notes payable, net	2,956,833	2,964,572
Unsecured senior notes, net	8,390,708	7,544,697
Unsecured line of credit	0	0
Unsecured term loan, net	$ 498,700	498,488
Number of VIEs that are consolidated	6
Carrying Amount [Member]
Summary Of Significant Accounting Policies [Line Items]
Related party note receivable	$ 80,000	80,000
Note receivable	19,718	19,468
Note and Related Party Receivables	99,718	99,468
Mortgage notes payable, net	2,956,833	2,964,572
Unsecured senior notes, net	8,390,708	7,544,697
Unsecured line of credit	0	0
Unsecured term loan, net	498,700	498,488
Total	11,846,241	11,007,757
Estimated Fair Value [Member]
Summary Of Significant Accounting Policies [Line Items]
Related party note receivable	80,321	80,000
Note receivable	18,205	19,468
Note and Related Party Receivables	98,526	99,468
Mortgage notes payable, net	3,013,338	2,903,925
Unsecured senior notes, net	8,745,888	7,469,338
Unsecured line of credit	0	0
Unsecured term loan, net	500,673	500,783
Total	$ 12,259,899	$ 10,874,046

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The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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