Other Liabilities (Notes)

12 Months Ended

Dec. 31, 2019

Other long-term liabilities

The following is a summary of the components of "Other long-term liabilities" as presented on the Company's consolidated balance sheet. The table below also gives effect to the Historical Adjustments, as discussed in note 2. See also note 3.



	December 31,
	2019		2018
			(As Restated)
Deferred rental revenues	$	1,814	$	1,618
Deferred ground lease payable^(a)	—		603
Above-market leases for land interests, net^(a)	—		181
Deferred credits, net	434		499
Asset retirement obligation	227		192
Deferred income tax liabilities	8		7
Other long-term liabilities	33		10
Total	$	2,516	$	3,110


(a)	See "Recently Adopted Accounting Pronouncements" in note 3 for a discussion of the recently adopted new lease standard, including with respect to deferred ground lease payable and above-market leases previously classified as other long-term liabilities.

Pursuant to its ground lease, easement and leased facility agreements, the Company has the obligation to perform certain asset retirement activities, including requirements upon contract termination to remove communications infrastructure or remediate the space upon which its communications infrastructure resides. Accretion expense related to liabilities for retirement obligations amounted to $15 million, $14 million and $13 million for the years ended December 31, 2019, 2018 and 2017, respectively. As of December 31, 2019, the estimated undiscounted future cash outlay for asset retirement obligations was approximately $1.0 billion. See note 3.

For the years ended December 31, 2018 and 2017, the Company recorded $18 million and $19 million, respectively, as a decrease to "Site rental costs of operations" for the amortization of above-market leases for land interests under the Company's towers. Effective January 1, 2019, these above-market leases were de-recognized and reclassified from "Other long-term liabilities" into the "Operating lease right-of-use assets" on the Company's consolidated balance sheet. See "Recently Adopted Accounting Pronouncements" in note 3 for a discussion of the recently adopted new lease standard.

For the years ended December 31, 2019, 2018 and 2017, the Company recognized $65 million, $69 million and $37 million, respectively, in "Site rental revenues" related to the amortization of below-market tenant leases. The following table summarizes the estimated annual amounts related to below-market tenant leases expected to be amortized into site rental revenues for the years ending December 31, 2020 to 2024 are as follows:



	Years Ending December 31,
	2020		2021		2022		2023		2024
Below-market tenant leases	$	57	$	53	$	49	$	45	$	41

Other accrued liabilities

Other accrued liabilities included accrued payroll and other accrued compensation of $174 million and $157 million, respectively, as of December 31, 2019 and 2018.