v3.25.4
Business Combinations - Narrative (Details)
 3 Months Ended 12 Months Ended
Aug. 01, 2025
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tower_site
Jul. 22, 2025
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agreement
Jun. 30, 2025
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Mar. 03, 2025
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Feb. 18, 2025
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Feb. 03, 2025
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May 24, 2024
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May 01, 2024
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shares
Apr. 30, 2024
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Mar. 09, 2023
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Dec. 31, 2024
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Dec. 31, 2025
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Dec. 31, 2024
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Dec. 31, 2023
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Aug. 05, 2025
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Dec. 20, 2024
Business Combination [Line Items]                                
Goodwill                     $ 13,005,000,000 $ 13,678,000,000 $ 13,005,000,000 $ 12,234,000,000    
Short-term debt assumed for financing of property and equipment                       1,653,000,000 0 $ 0    
Principal Issuances                       13,827,000,000        
EIP receivables                     4,379,000,000 4,997,000,000 4,379,000,000      
Preliminary goodwill from the Ka’ena Acquisition in 2024                         771,000,000      
Senior Notes                                
Business Combination [Line Items]                                
Principal Issuances                       $ 10,827,000,000        
6.700% Senior Notes due 2033 | Senior Notes                                
Business Combination [Line Items]                                
Principal Issuances                             $ 489,000,000  
Interest rate, stated percentage                       6.70%     6.70%  
6.250% Senior Notes due 2069 | Senior Notes                                
Business Combination [Line Items]                                
Principal Issuances                             $ 393,000,000  
Interest rate, stated percentage                       6.25%     6.25%  
5.500% Senior Notes due March 2070 | Senior Notes                                
Business Combination [Line Items]                                
Principal Issuances                             $ 401,000,000  
Interest rate, stated percentage                       5.50%     5.50%  
5.500% Senior Notes due June 2070 | Senior Notes                                
Business Combination [Line Items]                                
Principal Issuances                             $ 395,000,000  
Interest rate, stated percentage                       5.50%     5.50%  
Ka Ena Corporation | Merger And Unit Purchase Agreement                                
Business Combination [Line Items]                                
Business acquisition, outstanding (percent)                   100.00%            
Total consideration transferred     $ 1,350,000,000             $ 1,350,000,000            
Business acquisition, cash acquired (percent)                   39.00%            
Business acquisition, common shares acquired (percent)                   61.00%            
Ka Ena Corporation | Merger and Unit Purchase Agreement, Amendment No. 1                                
Business Combination [Line Items]                                
Total consideration transferred               $ 1,141,000,000                
Upfront payment transferred               $ 420,000,000                
Upfront payment, number of common shares transferred (in shares) | shares               3,264,952                
Upfront payment, transferred shares value                 $ 536,000,000              
Fair value of upfront payment, net               $ 956,000,000                
Business combination, contingent consideration, liability, deferred               27,000,000                
Upfront payment, customary adjustments                     17,000,000          
Additional upfront payment to be paid               420,000,000                
Business combination, potential earnout payment               251,000,000                
Business combination, contingent consideration liability               191,000,000                
Business combination, potential earnout payment for services               169,000,000                
Liabilities for deferred consideration                     202,000,000 $ 242,000,000 202,000,000      
Liabilities for post-acquisition                     $ 80,000,000 157,000,000 $ 80,000,000      
Goodwill               777,000,000                
Goodwill expected to be tax deductible               121,000,000                
Business acquisition, cash transferred               396,000,000                
Increase in deferred tax liabilities               83,000,000                
Accounts receivable               34,000,000                
Total liabilities assumed               506,000,000                
Ka Ena Corporation | Merger and Unit Purchase Agreement, Amendment No. 1 | Customer Relationships                                
Business Combination [Line Items]                                
Finite-lived, fair value               $ 545,000,000                
Lease space agreement term (years)               6 years                
Ka Ena Corporation | Merger and Unit Purchase Agreement, Amendment No. 1 | Tradenames                                
Business Combination [Line Items]                                
Finite-lived, fair value               $ 70,000,000                
Lease space agreement term (years)               8 years                
Ka Ena Corporation | Merger and Unit Purchase Agreement, Amendment No. 1 | Other Intangible Assets                                
Business Combination [Line Items]                                
Finite-lived, fair value               $ 125,000,000                
Lease space agreement term (years)               4 years                
UScellular Wireless Assets Operations                                
Business Combination [Line Items]                                
Total consideration transferred $ 2,855,000,000                              
Goodwill 219,000,000                              
Goodwill expected to be tax deductible 32,000,000                              
Business acquisition, cash transferred 2,811,000,000                              
Short-term debt assumed for financing of property and equipment                       $ 1,700,000,000        
Short-term debt assumed for financing of property and equipment at fair value $ 1,700,000,000                              
Lessee leasing arrangements, operating leases, term of contract (years) 30 months                              
Spectrum licenses $ 1,730,000,000                              
Accounts receivable 317,000,000                              
EIP receivables 891,000,000                              
Accounts receivable unpaid principal balances 328,000,000                              
EIP receivable unpaid principal balance 1,100,000,000                              
Total liabilities assumed 3,772,000,000                              
UScellular Wireless Assets Operations | Customer Relationships                                
Business Combination [Line Items]                                
Finite-lived, fair value $ 379,000,000                              
Lease space agreement term (years) 10 years                              
UScellular Wireless Assets Operations | Tradenames                                
Business Combination [Line Items]                                
Finite-lived, fair value $ 18,000,000                              
Lease space agreement term (years) 1 year                              
UScellular Wireless Assets Operations | Purchase Agreement                                
Business Combination [Line Items]                                
Payments for asset acquisition             $ 4,400,000,000                  
Asset acquisition, maximum transferred liabilities incurred             $ 2,000,000,000                  
Business acquisition, cash transferred $ 2,800,000,000                              
Number of towers to be extended tenancy term | tower_site 600                              
Lessee leasing arrangements, operating leases, term of contract (years) 15 years                              
UScellular Wireless Assets Operations | Master License Agreement                                
Business Combination [Line Items]                                
Principal Issuances                             $ 1,700,000,000  
Number of towers retained | tower_site 2,100                              
Number of towers leased on interim basis | tower_site 1,800                              
Operating lease right-of-use assets $ 1,000,000,000.0                              
Operating lease liabilities 1,000,000,000.0                              
Deferred tax assets 261,000,000                              
Increase in deferred tax liabilities $ 261,000,000                              
Vistar Media Inc.                                
Business Combination [Line Items]                                
Business acquisition, outstanding (percent)                               100.00%
Total consideration transferred           $ 617,000,000                    
Goodwill           343,000,000                    
Increase in deferred tax liabilities           61,000,000                    
Accounts receivable           157,000,000                    
Total consideration transferred, including settlements of preexisting relationships           621,000,000                    
Total liabilities assumed           193,000,000                    
Vistar Media Inc. | Customer Relationships                                
Business Combination [Line Items]                                
Finite-lived, fair value           201,000,000                    
Vistar Media Inc. | Tradenames                                
Business Combination [Line Items]                                
Finite-lived, fair value           8,000,000                    
Vistar Media Inc. | Other Intangible Assets                                
Business Combination [Line Items]                                
Finite-lived, fair value           $ 55,000,000                    
Vistar Media Inc. | Merger and Unit Purchase Agreement, Amendment No. 1 | Customer Relationships                                
Business Combination [Line Items]                                
Lease space agreement term (years)           10 years                    
Vistar Media Inc. | Merger and Unit Purchase Agreement, Amendment No. 1 | Tradenames                                
Business Combination [Line Items]                                
Lease space agreement term (years)           4 years                    
Vistar Media Inc. | Merger and Unit Purchase Agreement, Amendment No. 1 | Other Intangible Assets                                
Business Combination [Line Items]                                
Lease space agreement term (years)           4 years                    
Blis Holdco Limited                                
Business Combination [Line Items]                                
Business acquisition, outstanding (percent)         100.00%                      
Total consideration transferred         $ 174,000,000                      
Business acquisition, cash transferred       $ 180,000,000                        
Total assets acquired, including goodwill         264,000,000                      
Total liabilities assumed         90,000,000                      
Preliminary goodwill from the Ka’ena Acquisition in 2024         $ 105,000,000                      
Farmers Cellular Telephone Company Acquisition | Purchase Agreement                                
Business Combination [Line Items]                                
Number of separate asset purchase agreements | agreement   3                            
Business acquisition, cash transferred   $ 175,000,000