Debt - Summary of Debt (Details) - USD ($)		6 Months Ended
		Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total debt	[1]	$ 21,416,444,000	$ 19,643,806,000
Less: unamortized debt issuance costs		(367,028,000)	(314,763,000)
Total debt, net of unamortized debt issuance costs		21,049,416,000	19,329,043,000
Less—current portion including commercial paper		(970,627,000)	(1,371,087,000)
Long-term portion		$ 20,078,789,000	$ 17,957,956,000
Weighted average interest rate		5.98%	6.02%
Unsecured UK Commercial paper
Debt Instrument [Line Items]
Long-term debt, gross		$ 0	$ 409,319,000
Total fixed rate debt
Debt Instrument [Line Items]
Long-term debt, gross		12,387,412,000	11,024,809,000
Unsecured senior notes
Debt Instrument [Line Items]
Long-term debt, gross		$ 4,610,341,000	2,464,994,000
Unsecured senior notes | Minimum
Debt Instrument [Line Items]
Interest rate	[2]	3.70%
Unsecured senior notes | Maximum
Debt Instrument [Line Items]
Interest rate	[2]	9.13%
Secured senior notes
Debt Instrument [Line Items]
Long-term debt, gross		$ 3,252,702,000	3,895,166,000
Secured senior notes | Minimum
Debt Instrument [Line Items]
Interest rate	[2]	10.88%
Secured senior notes | Maximum
Debt Instrument [Line Items]
Interest rate	[2]	11.50%
Unsecured term loans
Debt Instrument [Line Items]
Long-term debt, gross		$ 3,017,735,000	3,210,161,000
Unsecured term loans | Minimum
Debt Instrument [Line Items]
Interest rate	[2]	2.53%
Unsecured term loans | Maximum
Debt Instrument [Line Items]
Interest rate	[2]	5.41%
Convertible notes
Debt Instrument [Line Items]
Long-term debt, gross		$ 1,506,634,000	1,454,488,000
Convertible notes | Minimum
Debt Instrument [Line Items]
Interest rate	[2]	2.88%
Convertible notes | Maximum
Debt Instrument [Line Items]
Interest rate	[2]	4.25%
Total variable rate debt
Debt Instrument [Line Items]
Long-term debt, gross		$ 8,601,277,000	8,405,632,000
Unsecured revolving credit facilities
Debt Instrument [Line Items]
Long-term debt, gross	[3]	2,999,342,000	3,289,000,000
Maximum borrowing capacity		$ 3,200,000,000
Unsecured revolving credit facilities | Minimum
Debt Instrument [Line Items]
Current interest rate	[2],[3]	1.38%
Unsecured revolving credit facilities | Maximum
Debt Instrument [Line Items]
Current interest rate	[2],[3]	1.78%
Unsecured revolving credit facilities | Unsecured Revolving Credit Facility Due 2024
Debt Instrument [Line Items]
Current interest rate		1.45%
Maximum borrowing capacity		$ 1,900,000,000
Facility fee		0.20%
Unsecured revolving credit facilities | Unsecured Revolving Credit Facility Due 2024 | LIBOR | Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		1.30%
Unsecured revolving credit facilities | Unsecured Revolving Credit Facility Due 2024
Debt Instrument [Line Items]
Current interest rate		1.85%
Maximum borrowing capacity		$ 1,300,000,000
Unsecured revolving credit facilities | Unsecured Revolving Credit Facility Due 2024 | Maximum
Debt Instrument [Line Items]
Facility fee		0.30%
Unsecured revolving credit facilities | Unsecured Revolving Credit Facility Due 2024 | LIBOR | Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		1.70%
USD unsecured term loan
Debt Instrument [Line Items]
Long-term debt, gross		$ 4,887,153,000	4,002,249,000
USD unsecured term loan | Minimum
Debt Instrument [Line Items]
Current interest rate	[2]	0.59%
USD unsecured term loan | Maximum
Debt Instrument [Line Items]
Current interest rate	[2]	3.33%
Euro unsecured term loan
Debt Instrument [Line Items]
Long-term debt, gross		$ 714,782,000	705,064,000
Euro unsecured term loan | Minimum
Debt Instrument [Line Items]
Current interest rate	[2]	1.15%
Euro unsecured term loan | Maximum
Debt Instrument [Line Items]
Current interest rate	[2]	2.25%
Finance lease liabilities
Debt Instrument [Line Items]
Long-term debt, gross		$ 427,755,000	$ 213,365,000

[1] At June 30, 2021 and December 31, 2020, the weighted average interest rate for total debt was 5.98% and 6.02%, respectively.

[2] Interest rates based on outstanding loan balance as of June 30, 2021 and, for variable rate debt, include either LIBOR or EURIBOR plus the applicable margin.

[3] Includes $1.9 billion facility and $1.3 billion facility, the vast majority of which is due in 2024. Our $1.9 billion facility accrues interest at LIBOR plus a maximum interest rate margin of 1.30%, which interest was 1.45% as of June 30, 2021 and is subject to a facility fee of a maximum of 0.20%. Our $1.3 billion facility accrues interest at LIBOR plus a maximum interest rate margin of 1.70%, which interest was 1.85% as of June 30, 2021 and is subject to a facility fee of a maximum of 0.30%.