Investments in Unconsolidated Entities and International Investments - Repayments of Mortgages (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Scheduled principal repayments on mortgage indebtedness
2020	$ 2,857,060
2021	1,541,478
2022	2,872,980
2023	1,868,669
2024	2,896,466
Thereafter	12,208,803
Total principal maturities	24,245,456
Debt issuance costs	(101,280)	$ (96,175)
Equity Method Investees excluding Klepierre, Aeropostale, ABG, HBS and RGG \| Unconsolidated properties
Scheduled principal repayments on mortgage indebtedness
2020	946,309
2021	2,476,864
2022	1,927,938
2023	1,267,179
2024	2,297,118
Thereafter	6,512,206
Total principal maturities	15,427,614
Debt issuance costs	(35,833)
Total mortgages	$ 15,391,781	$ 15,235,415
Weighted average interest rate (as a percent)	3.94%
Equity Method Investees excluding Klepierre, Aeropostale, ABG, HBS and RGG \| Unconsolidated properties \| Minimum
Scheduled principal repayments on mortgage indebtedness
Interest rate on debt (as a percent)	0.18%
Equity Method Investees excluding Klepierre, Aeropostale, ABG, HBS and RGG \| Unconsolidated properties \| Maximum
Scheduled principal repayments on mortgage indebtedness
Interest rate on debt (as a percent)	10.53%

The amount of mortgage liabilities reported by an equity method investment of the entity.

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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.

+ References

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

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Weighted average interest rate of debt outstanding.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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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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 in the next 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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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 in 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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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 in the fourth 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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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 in the third 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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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 in the second 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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