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

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

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

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Weighted average interest rate of debt outstanding.

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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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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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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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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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The excess of the (1) fair value of consideration transferred to the holders of a security in excess of (2) the carrying amount of the security reported on the registrant's balance sheet, which will be deducted from net earnings to derive net earnings available to common shareholders. This amount is generally an adjustment considered in the computation of earnings per share.

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The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

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Debt Extinguishment or Debt Prepayment Cost

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The cash outflow for the early payment of the principal amount on outstanding mortgage debt.

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The effective rate on par for debt issued during the period.

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Debt - Narratives (Details)			3 Months Ended		6 Months Ended
Debt - Narratives (Details)	Mar. 08, 2021 EUR (€)	Feb. 25, 2021 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 EUR (€)	Dec. 31, 2020 USD ($)	Feb. 20, 2020 USD ($)	Feb. 20, 2020 EUR (€)	Feb. 20, 2020 GBP (£)
Senior Unsecured Credit Facility
Maximum borrowing capacity			$ 2,750,000,000		$ 2,750,000,000				$ 2,100,000,000
Prepayments of mortgage principal					426,907,000	$ 0
Financing cost			$ 28,688,000		$ 28,688,000
Non Recourse Mortgage
Weighted average interest rate (in percentage)			4.10%		4.10%		4.10%
Repayments of non recourse mortgage loan					$ 20,239,000	36,598,000
Increase (decrease) in value of balance sheet item due to foreign currency translation			$ 5,973,000	$ 13,847,000	(7,929,000)	$ (38,353,000)
Unamortized discount			33,386,000		33,386,000
Merged Entities
Non Recourse Mortgage
Unamortized discount			$ 3,800,000		$ 3,800,000
Fixed interest rate
Non Recourse Mortgage
Weighted average interest rate (in percentage)			4.70%		4.70%		4.70%
Variable interest rate
Non Recourse Mortgage
Weighted average interest rate (in percentage)			2.10%		2.10%		2.10%
Unsecured senior notes
Senior Unsecured Credit Facility
Principal Amount			$ 5,600,000,000		$ 5,600,000,000
Financing cost			28,500,000		28,500,000			$ 23,800,000
Non Recourse Mortgage
Unamortized discount			28,600,000		28,600,000			22,500,000
Unsecured senior notes \| 2.250% Senior Notes due 2033
Senior Unsecured Credit Facility
Principal Amount		$ 425,000,000.0	$ 425,000,000		$ 425,000,000
Stated interest rate (percentage)		2.25%	2.25%		2.25%		2.25%
Price of par value (percentage)		98.722%
Debt instrument term (years)		12 years 1 month 6 days
Unsecured senior notes \| 0.950% Senior Notes due 2030
Senior Unsecured Credit Facility
Principal Amount \| €	€ 525,000,000.0						€ 525,000,000.0
Stated interest rate (percentage)	0.95%		0.95%		0.95%		0.95%
Price of par value (percentage)	99.335%
Debt instrument term (years)	9 years 2 months 12 days
Redemption premium					$ 26,200,000
Loss on extinguishment of debt					28,200,000
Non Recourse Mortgage
Loss on extinguishment of debt					$ 28,200,000
Unsecured senior notes \| 2.0% Senior Notes due 2023
Senior Unsecured Credit Facility
Principal Amount \| €							€ 500,000,000.0
Stated interest rate (percentage)			2.00%		2.00%		2.00%
Unsecured senior notes \| Euro Senior Note 0.950% Due 2030
Senior Unsecured Credit Facility
Financing cost			$ 8,200,000		$ 8,200,000
Unsecured senior notes \| Government bond yield \| Minimum
Senior Unsecured Credit Facility
Variable interest rate (percentage)					0.30%
Unsecured senior notes \| Government bond yield \| Maximum
Senior Unsecured Credit Facility
Variable interest rate (percentage)					0.35%
Non-Recourse Debt
Senior Unsecured Credit Facility
Prepayments of mortgage principal					$ 426,900,000
Loss on extinguishment of debt					$ 31,900,000
Non Recourse Mortgage
Weighted average interest rate (in percentage)			5.10%	4.50%	5.10%	4.50%	5.10%
Repayments of non recourse mortgage loan					$ 3,000,000.0	$ 10,200,000
Loss on extinguishment of debt					31,900,000
Debt extinguishment cost					31,800,000
Increase (decrease) in value of balance sheet item due to foreign currency translation					(106,800,000)
Unsecured Revolving Credit Facility
Senior Unsecured Credit Facility
Line of credit facility, available			$ 1,500,000,000		$ 1,500,000,000
Debt Instrument borrowing capacity fee (percentage)					0.20%
Unsecured Revolving Credit Facility \| USD
Senior Unsecured Credit Facility
Maximum borrowing capacity									$ 1,800,000,000
Unsecured Term Loans \| GBP
Senior Unsecured Credit Facility
Maximum borrowing capacity \| £											£ 150,000,000.0
Non Recourse Mortgage
Unamortized discount			1,000,000.0		$ 1,000,000.0			$ 1,200,000
Unsecured Term Loans \| EUR
Senior Unsecured Credit Facility
Maximum borrowing capacity \| €										€ 96,500,000
Standby Letters of Credit
Senior Unsecured Credit Facility
Line of credit facility, available			$ 19,200,000		$ 19,200,000