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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Face (par) amount of debt instrument at time of issuance.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References

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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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- Definition

Senior unsecured notes and secured debt.

+ References

No definition available.

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Senior Unsecured Notes and Secured Debt (Annual Principal Payments Due on Debt Obligations) (Details)	12 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2019 GBP (£)	Dec. 31, 2019 CAD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Principal payments due on debt obligations
2020	$ 354,329,000
2021	439,176,000
2022	431,876,000
2023	2,260,249,000
2024	1,654,533,000
Thereafter	8,280,741,000
Totals	13,420,904,000
Senior Unsecured Notes
Principal payments due on debt obligations
2020	0
2021	0
2022	10,000,000
2023	1,792,871,000
2024	1,350,000,000
Thereafter	7,274,691,000
Totals	$ 10,427,562,000			$ 9,699,984,000	$ 8,417,447,000	$ 8,260,038,000
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	2.40%	2.40%	2.40%
Secured Debt
Principal payments due on debt obligations
2020	$ 354,329,000
2021	439,176,000
2022	421,876,000
2023	467,378,000
2024	304,533,000
Thereafter	1,006,050,000
Totals	2,993,342,000			$ 2,485,711,000	$ 2,618,408,000	$ 3,465,066,000
Senior Unsecured Notes and Secured Debt Textual [Abstract]
Carrying value of properties securing the debt	$ 6,550,033,000
Secured Debt \| Maximum
Senior Unsecured Notes and Secured Debt Textual [Abstract]
Interest rate	12.00%	12.00%	12.00%
Secured Debt \| Minimum
Senior Unsecured Notes and Secured Debt Textual [Abstract]
Interest rate	1.25%	1.25%	1.25%
Canadian Denominated Unsecured Term Loan
Senior Unsecured Notes and Secured Debt Textual [Abstract]
Maximum borrowing capacity	$ 192,871,000		$ 250,000,000
Effective rate	2.93%	2.93%	2.93%
Unsecured Term Credit Facility
Senior Unsecured Notes and Secured Debt Textual [Abstract]
Maximum borrowing capacity	$ 500,000,000
Effective rate	2.66%	2.66%	2.66%
UK Debt Due 2028
Senior Unsecured Notes and Secured Debt Textual [Abstract]
Interest rate	4.80%	4.80%	4.80%
Face amount	$ 729,795,000	£ 550,000,000
UK Debt Due 2034
Senior Unsecured Notes and Secured Debt Textual [Abstract]
Interest rate	4.50%	4.50%	4.50%
Face amount	$ 663,450,000	£ 500,000,000
Canadian Dealer Offered Rate \| Canadian Denominated Unsecured Term Loan
Senior Unsecured Notes and Secured Debt Textual [Abstract]
Interest rate margin	0.90%
LIBOR \| Unsecured Term Credit Facility
Senior Unsecured Notes and Secured Debt Textual [Abstract]
Interest rate margin	0.90%
2.95% Senior Unsecured Notes Due 2027 \| Senior Unsecured Notes
Senior Unsecured Notes and Secured Debt Textual [Abstract]
Interest rate	2.95%	2.95%	2.95%
Face amount	$ 231,446,000		$ 300,000,000