Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Name:	us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Revenues	$ 17,671	$ 10,979	$ 28,784	$ 22,059
Postpaid phone revenues
Disaggregation of Revenue [Line Items]
Revenues	9,341	5,287	14,918	10,470
Postpaid other revenues
Disaggregation of Revenue [Line Items]
Revenues	618	326	928	636
Postpaid service revenues
Disaggregation of Revenue [Line Items]
Revenues	9,959	5,613	15,846	11,106
Wireless service revenues \| Sprint
Disaggregation of Revenue [Line Items]
Revenues	211		211
Equipment revenues from the lease of mobile communication devices
Disaggregation of Revenue [Line Items]
Revenues	$ 1,421	$ 143	$ 1,586	$ 304