The following table summarizes the components of accounts payable, accrued expenses, and other liabilities as of March 31, 2024 and December 31, 2023 (in thousands):


	March 31, 2024		December 31, 2023
Accounts payable and accrued expenses	$	432,296	$	524,439
Accrued construction	643,456		606,333
Acquired below-market leases	290,614		322,040
Conditional asset retirement obligations	55,958		53,083
Deferred rent liabilities	13,365		15,183
Operating lease liability	381,578		382,883
Unearned rent and tenant security deposits	561,795		548,529
Other liabilities	124,769		158,453
Total	$	2,503,831	$	2,610,943

As of March 31, 2024 and December 31, 2023, our conditional asset retirement obligations liability primarily consisted of the soil and groundwater remediation liabilities associated with certain of our properties. Some of our properties may contain asbestos or may be subjected to other hazardous or toxic substances, which, under certain conditions, requires remediation. We engage independent environmental consultants to conduct Phase I or similar environmental assessments at our properties. This type of assessment generally includes a site inspection, interviews, and a public records review; asbestos, lead-based paint, and mold surveys; subsurface sampling; and other testing. We recognize a liability for the fair value of a conditional asset retirement obligation (including asbestos) when the fair value of the liability can be reasonably estimated. In addition, environmental laws and regulations subject our tenants, and potentially us, to liability that may result from our tenants’ routine handling of hazardous substances and wastes as part of their operations at our properties. These assessments and investigations of our properties have not to date revealed any additional environmental liability we believe would have a material adverse effect on our business and financial statements or that would require additional disclosures or recognition in our consolidated financial statements.