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Revenue from Contracts with Customers - Schedule of Contract Assets Rollforward (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Capitalized Cost To Fulfill Customer Contracts |  |  |  |
Change in Capitalized Contract Costs |  |  |  |
Balance at beginning of period | $ 273 | $ 264 | $ 424 | $ 370
Additions | 440 | 400 | 1,267 | 1,166
Amortization | (392) | (367) | (1,384) | (1,235)
Impairment | 0 | 0 | 0 | 0
Foreign currency translation and other | (1) | 5 | 13 | 1
Balance at end of period | 320 | 302 | 320 | 302
Capitalized Cost To Obtain Customer Contracts |  |  |  |
Change in Capitalized Contract Costs |  |  |  |
Balance at beginning of period | 187 | 196 | 207 | 195
Additions | 4 | 19 | 31 | 51
Amortization | (1) | (13) | (54) | (40)
Impairment | 0 | 0 | 0 | 0
Foreign currency translation and other | 0 | 0 | 6 | (4)
Balance at end of period | $ 190 | $ 202 | $ 190 | $ 202

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- Definition Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 340 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479483/340-40-50-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147476148/220-40-50-22 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147476148/220-40-50-22 + Details
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