Amount of short-term and long-term debt and lease obligation.

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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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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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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 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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Non Recourse Debt [Abstract]

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

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Revolving Line Of Credit [Abstract]

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Debt - Narratives (Details)	3 Months Ended		6 Months Ended
Debt - Narratives (Details)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 EUR (€)	Jun. 30, 2020 GBP (£)	Mar. 27, 2020 USD ($)	Mar. 27, 2020 EUR (€)	Feb. 20, 2020 USD ($)	Feb. 20, 2020 GBP (£)	Feb. 19, 2020 USD ($)	Dec. 31, 2019 USD ($)
Senior Unsecured Credit Facility
Maximum borrowing capacity	$ 2,750,000,000		$ 2,750,000,000						$ 2,100,000,000		$ 1,850,000,000
Debt outstanding	314,518,000		314,518,000									$ 201,267,000
Financing cost	21,334,000		21,334,000						10,000,000.0
Non Recourse Mortgage
Repayments of non recourse mortgage loan			36,598,000	$ 57,358,000
Prepayments of mortgage principal			0	493,317,000
Decrease in value of balance sheet item due to foreign currency translation	(13,847,000)	$ 4,187,000	38,353,000	$ 4,360,000
Unamortized discount	25,219,000		25,219,000
Merged Entities
Non Recourse Mortgage
Unamortized discount	$ 5,100,000		$ 5,100,000
Fixed interest rate
Non Recourse Mortgage
Weighted average interest rate	4.90%		4.90%		4.90%	4.90%
Variable interest rate
Non Recourse Mortgage
Weighted average interest rate	2.90%		2.90%		2.90%	2.90%
Unsecured senior notes
Senior Unsecured Credit Facility
Financing cost	$ 20,800,000		$ 20,800,000									22,800,000
Principal Amount	4,400,000,000		4,400,000,000
Non Recourse Mortgage
Unamortized discount	$ 18,800,000		$ 18,800,000									20,500,000
Non-Recourse Debt
Non Recourse Mortgage
Weighted average interest rate	4.50%	5.10%	4.50%	5.10%	4.50%	4.50%
Repayments of non recourse mortgage loan			$ 10,200,000	$ 18,800,000
Unsecured senior notes
Non Recourse Mortgage
Unamortized discount	$ 18,800,000		$ 18,800,000
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%
Unsecured Revolving Credit Facility
Senior Unsecured Credit Facility
Debt outstanding	22,366,000		$ 22,366,000									201,267,000
Line of credit facility, available	1,800,000,000		$ 1,800,000,000
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 Revolving Credit Facility \| GBP
Senior Unsecured Credit Facility
Debt outstanding	0		$ 0									47,534,000
Unsecured Revolving Credit Facility \| EUR
Senior Unsecured Credit Facility
Debt outstanding	0		0									131,438,000
Unsecured Term Loans
Senior Unsecured Credit Facility
Debt outstanding	292,152,000		292,152,000									0
Unsecured Term Loans \| GBP
Senior Unsecured Credit Facility
Maximum borrowing capacity \| £										£ 150,000,000.0
Debt outstanding	184,091,000		184,091,000			£ 150,000,000.0			$ 193,100,000			0
Non Recourse Mortgage
Unamortized discount	1,300,000		1,300,000
Unsecured Term Loans \| EUR
Senior Unsecured Credit Facility
Maximum borrowing capacity \| €								€ 96,500,000
Debt outstanding	$ 108,061,000		108,061,000		€ 96,500,000		$ 105,900,000					$ 0
Non-Recourse Debt
Non Recourse Mortgage
Prepayments of mortgage principal				$ 493,300,000
Decrease in value of balance sheet item due to foreign currency translation			$ 24,900,000