Mortgage and Other Indebtedness, Net (Scheduled Principal Payments) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of principal repayments [Abstract]
2017	$ 134,159
2018	667,320
2019	329,846
2020	551,004
2021	498,168
Thereafter	2,067,125
Mortgage and other indebtedness	4,247,622
Unamortized premiums and discounts, net	(12,172)
Unamortized deferred financing costs	(19,272)	$ (17,855)
Total mortgage and other indebtedness, net	$ 4,216,178	$ 4,465,294

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

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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, 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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