Investments in real estate - Acquired leases (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Acquired below-market leases
Real Estate Properties [Line Items]
Amortization of intangible assets	$ 96,900	$ 78,000	$ 57,700
Weighted average amortization period	6 years 3 months 18 days
Values of acquired leases
Finite-Lived Intangible Assets, Gross	$ 696,875	730,441
Accumulated amortization	(374,835)	(312,785)
Value of intangible assets, net	322,040	417,656
Estimated annual amortization
2024	86,595
2025	38,796
2026	30,526
2027	29,995
2028	18,000
Thereafter	118,128
Acquired-in-Place Leases
Real Estate Properties [Line Items]
Amortization of intangible assets	$ 160,600	169,500	$ 146,600
Weighted average amortization period	8 years 1 month 6 days
Values of acquired leases
Finite-Lived Intangible Assets, Gross	$ 1,115,259	1,150,690
Accumulated amortization	(653,646)	(535,052)
Value of intangible assets, net	461,613	$ 615,638
Estimated annual amortization
2024	107,883
2025	75,610
2026	58,029
2027	48,279
2028	36,171
Thereafter	$ 135,641

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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