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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

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Amount of increase (decrease) in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Revenue from Contracts with Customers - Contract Balances (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Apr. 01, 2020	Dec. 31, 2019
Change in Contract with Customer, Asset and Liability [Abstract]
Contract Assets	$ 197		$ 197			$ 63
Contract Liabilities	845		845			560
Change in contract assets included in other current assets			134
Change in contracts liabilities included in deferred revenue			285
Current portion of contract assets	168		168			50
Amounts included in the beginning of year contract liability balance	10	$ 43	538	$ 603
Disaggregation of Revenue [Line Items]
Contract Assets	197		197			63
Contract Liabilities	$ 845		$ 845			$ 560
Sprint
Change in Contract with Customer, Asset and Liability [Abstract]
Contract Assets					$ 154
Contract Liabilities					252
Disaggregation of Revenue [Line Items]
Contract Assets					154
Contract Liabilities					$ 252