| Leases | 6 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Leases [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Leases | Leases We have operating and finance leases for offices, terrestrial repeaters, data centers and certain equipment.  Our leases have remaining lease terms of less than 1 year to 17 years, some of which may include options to extend the leases for up to 5 years, and some of which may include options to terminate the leases within 1 year.  We elected the practical expedient to account for the lease and non-lease components as a single component.  Additionally, we elected the practical expedient to not recognize right-of-use assets or lease liabilities for short-term leases, which are those leases with a term of twelve months or less at the lease commencement date.  The components of lease expense were as follows:  
 During the six months ended June 30, 2021, we ceased using certain leased locations and recorded an impairment charge of $18 to write down the carrying value of the right-of-use assets for these locations to their estimated fair values.  Refer to Note 4 for additional information. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Leases | Leases We have operating and finance leases for offices, terrestrial repeaters, data centers and certain equipment.  Our leases have remaining lease terms of less than 1 year to 17 years, some of which may include options to extend the leases for up to 5 years, and some of which may include options to terminate the leases within 1 year.  We elected the practical expedient to account for the lease and non-lease components as a single component.  Additionally, we elected the practical expedient to not recognize right-of-use assets or lease liabilities for short-term leases, which are those leases with a term of twelve months or less at the lease commencement date.  The components of lease expense were as follows:  
 During the six months ended June 30, 2021, we ceased using certain leased locations and recorded an impairment charge of $18 to write down the carrying value of the right-of-use assets for these locations to their estimated fair values.  Refer to Note 4 for additional information. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||