The carrying amounts of external-use software development costs as of September 30, 2024 and December 31, 2023 were as follows:


	September 30, 2024		December 31, 2023

	(In thousands)
Gross carrying amount	$	245,155	$	239,038
Accumulated amortization	(185,598)		(172,379)
External-use software development costs, net (1)	$	59,557	$	66,659

(1) Included in other long-term assets in the Condensed Consolidated Balance Sheets.

The Company recorded $6.0 million and $7.1 million to cost of revenues for amortization of external-use software development costs for the three months ended September 30, 2024 and 2023, respectively, and $19.1 million and $21.9 million for the nine months ended September 30, 2024 and 2023, respectively.

The estimated future amortization expenses for external-use software development costs were as follows:


	September 30, 2024

	(In thousands)
Remaining three months of 2024	$	5,862
2025	20,545
2026	15,269
2027	9,336
2028	5,478
Thereafter	3,067
Total	$	59,557