Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Amount of assets pledged to secure a debt instrument.

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- Definition

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

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- Definition

Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services.

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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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- References

No definition available.

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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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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Senior unsecured notes and secured debt.

+ References

No definition available.

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Senior Unsecured Notes Issued

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No definition available.

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Senior Unsecured Notes and Secured Debt (Details) £ in Thousands, $ in Thousands, $ in Thousands	9 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2018 GBP (£)	Sep. 30, 2018 CAD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Principal payments due on debt obligations
2018	$ 170,742
2019	1,089,166
2020	828,600
2021	797,280
2022	825,832
Thereafter	8,521,831
Totals	12,233,451
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Senior unsecured notes	$ 9,655,022			$ 8,331,722
Debt instrument, basis spread on variable rate	0.825%
Unsecured term credit facility
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Senior unsecured notes	$ 500,000
Unsecured term credit facility \| London Interbank Offered Rate (LIBOR)
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Interest rate	3.07%	3.07%	3.07%
Debt instrument, basis spread on variable rate	0.90%
Senior Unsecured Notes
Principal payments due on debt obligations
2018	$ 0
2019	600,000
2020	689,662
2021	450,000
2022	600,000
Thereafter	7,414,034
Totals	$ 9,753,696			8,417,447	$ 8,404,393	$ 8,260,038
Senior Unsecured Notes \| Maximum
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Interest rate	6.50%	6.50%	6.50%
Senior Unsecured Notes \| Minimum
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Interest rate	2.73%	2.73%	2.73%
Secured Debt
Principal payments due on debt obligations
2018	$ 170,742
2019	489,166
2020	138,938
2021	347,280
2022	225,832
Thereafter	1,107,797
Totals	2,479,755			$ 2,618,408	$ 2,720,002	$ 3,465,066
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Carrying values of properties securing the debt	$ 5,303,414
Secured Debt \| Maximum
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Interest rate	7.93%	7.93%	7.93%
Secured Debt \| Minimum
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Interest rate	1.69%	1.69%	1.69%
3.35% senior unsecured note due 2020
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Guarantees	$ 232,162		$ 300,000
Canadian Denominated Unsecured Term Loan
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Senior unsecured notes	$ 193,469		$ 250,000
Canadian Denominated Unsecured Term Loan \| London Interbank Offered Rate (LIBOR)
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Debt instrument, basis spread on variable rate	0.90%
Canadian Denominated Unsecured Term Loan \| Canadian Denominated Unsecured Term Loan
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Interest rate	2.73%	2.73%	2.73%
UK Debt Due 2028
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Interest rate	4.80%	4.80%	4.80%
Senior unsecured notes issued amount	$ 717,915	£ 550,000
UK Debt Due 2034
Senior Unsecured Notes and Secured Debt (Textual) [Abstract]
Interest rate	4.50%	4.50%	4.50%
Senior unsecured notes issued amount	$ 652,650	£ 500,000