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

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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 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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Debt - Narratives (Details) £ in Millions	3 Months Ended
Debt - Narratives (Details) £ in Millions	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Mar. 31, 2020 EUR (€)	Mar. 31, 2020 GBP (£)	Mar. 27, 2020 USD ($)	Mar. 27, 2020 EUR (€)	Feb. 20, 2020 USD ($)	Feb. 20, 2020 EUR (€)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 EUR (€)
Senior Unsecured Credit Facility
Maximum borrowing capacity	$ 2,750,000,000						$ 2,100,000,000		$ 2,350,000,000
Debt outstanding	366,604,000								201,267,000
Financing cost	22,148,000						10,000,000.0
Line of credit facility, available	$ 1,700,000,000
Debt Instrument borrowing capacity fee (percentage)	0.20%
Non Recourse Mortgage
Repayments of non recourse mortgage loan	$ 21,117,000	$ 40,360,000
Prepayments of mortgage principal	0	199,579,000
Decrease in value of balance sheet item due to foreign currency translation	52,200,000	$ 173,000
Unamortized discount	26,344,000
Merged Entities
Non Recourse Mortgage
Unamortized discount	$ 5,600,000
Fixed interest rate
Non Recourse Mortgage
Weighted average interest rate	5.00%		5.00%	5.00%
Variable interest rate
Non Recourse Mortgage
Weighted average interest rate	2.90%		2.90%	2.90%
Unsecured senior notes
Senior Unsecured Credit Facility
Financing cost	$ 21,600,000								22,800,000
Principal Amount	4,400,000,000
Non Recourse Mortgage
Unamortized discount	$ 19,300,000								20,500,000
Non-Recourse Debt
Non Recourse Mortgage
Weighted average interest rate	4.50%	5.00%	4.50%	4.50%
Repayments of non recourse mortgage loan	$ 7,700,000	$ 18,800,000
Revolving Credit Facility
Senior Unsecured Credit Facility
Maximum borrowing capacity									1,500,000,000
Delayed Draw term loan
Senior Unsecured Credit Facility
Maximum borrowing capacity									100,000,000.0
Term Loan
Senior Unsecured Credit Facility
Maximum borrowing capacity \| €										€ 236,300,000
Unsecured senior notes
Non Recourse Mortgage
Unamortized discount	$ 19,300,000
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	$ 75,483,000								201,267,000
Unsecured Revolving Credit Facility \| USD
Senior Unsecured Credit Facility
Maximum borrowing capacity							1,800,000,000
Debt outstanding	10,000,000								0
Unsecured Revolving Credit Facility \| GBP
Senior Unsecured Credit Facility
Debt outstanding	0								47,534,000
Unsecured Revolving Credit Facility \| EUR
Senior Unsecured Credit Facility
Debt outstanding	43,276,000		€ 39,500,000						131,438,000
Unsecured Term Loans
Senior Unsecured Credit Facility
Debt outstanding	291,121,000								0
Unsecured Term Loans \| GBP
Senior Unsecured Credit Facility
Maximum borrowing capacity \| €								€ 150,000,000.0
Debt outstanding	$ 185,395,000			£ 150.0			$ 193,100,000		0
Variable interest rate (percentage)	0.95%
Unsecured Term Loans \| EUR
Senior Unsecured Credit Facility
Maximum borrowing capacity \| €						€ 96,500,000
Debt outstanding	$ 105,726,000		€ 96,500,000		$ 105,900,000				$ 0
Variable interest rate (percentage)	0.95%
Non Recourse Mortgage
Unamortized discount	$ (1,400,000)
Non-Recourse Debt
Non Recourse Mortgage
Prepayments of mortgage principal		$ 199,600,000
Decrease in value of balance sheet item due to foreign currency translation	$ 93,500,000