Investments in Unconsolidated Entities - Repayments of Mortgages (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Scheduled principal repayments on mortgage indebtedness
2017	$ 2,233,249
2018	802,806
2019	742,323
2020	3,563,396
2021	2,740,755
Thereafter	13,016,921
Total principal maturities	23,099,450
Net unamortized debt premium	(24,510)
Debt issuance costs	(97,836)	$ (85,491)
Total mortgages and unsecured indebtedness	22,977,104	$ 22,416,682
Unconsolidated properties
Scheduled principal repayments on mortgage indebtedness
2017	552,579
2018	418,221
2019	704,496
2020	3,180,236
2021	1,832,371
Thereafter	7,607,451
Total principal maturities	14,295,354
Net unamortized debt premium	3,337
Debt issuance costs	(61,115)
Total mortgages and unsecured indebtedness	$ 14,237,576
Weighted average interest rate (as a percent)	3.97%
Unconsolidated properties \| Minimum
Scheduled principal repayments on mortgage indebtedness
Interest rate on debt (as a percent)	0.26%
Unconsolidated properties \| Maximum
Scheduled principal repayments on mortgage indebtedness
Interest rate on debt (as a percent)	9.35%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount (premium).

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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 of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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