| Leases | 3 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Mar. 31, 2019 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| 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 19 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: 
 Supplemental cash flow information related to leases was as follows: 
 Supplemental balance sheet information related to leases was as follows: 
 
 
 
 Maturities of lease liabilities were as follows: 
 
As of March 31, 2019, we had entered into an additional operating lease for office space that has not yet commenced of $33.  This operating lease will commence in the second quarter of 2019 with a lease term of 11 years.
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| 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 19 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: 
 Supplemental cash flow information related to leases was as follows: 
 Supplemental balance sheet information related to leases was as follows: 
 
 
 
 Maturities of lease liabilities were as follows: 
 
As of March 31, 2019, we had entered into an additional operating lease for office space that has not yet commenced of $33.  This operating lease will commence in the second quarter of 2019 with a lease term of 11 years.
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