Segments and Geographic Information - Revenue and Profit by Segment (Details) - USD ($)	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Revenue	$ 1,744,000,000	$ 1,375,000,000
Cost of services	(739,000,000)
Segment gross profit	1,005,000,000
Sirius XM
Segment Reporting Information [Line Items]
Revenue	1,493,000,000
Cost of services	(569,000,000)
Segment gross profit	924,000,000
Pandora
Segment Reporting Information [Line Items]
Revenue	251,000,000
Cost of services	(170,000,000)
Segment gross profit	81,000,000
Subscriber revenue
Segment Reporting Information [Line Items]
Revenue	1,458,000,000	1,258,000,000
Subscriber revenue \| Sirius XM
Segment Reporting Information [Line Items]
Revenue	1,370,000,000
Subscriber revenue \| Pandora
Segment Reporting Information [Line Items]
Revenue	88,000,000
Advertising revenue
Segment Reporting Information [Line Items]
Revenue	209,000,000	42,000,000
Advertising revenue \| Sirius XM
Segment Reporting Information [Line Items]
Revenue	46,000,000
Advertising revenue \| Pandora
Segment Reporting Information [Line Items]
Revenue	163,000,000
Advertising revenue \| Elimination
Segment Reporting Information [Line Items]
Revenue	0
Equipment Revenue
Segment Reporting Information [Line Items]
Revenue	41,000,000	35,000,000
Cost of services	(6,000,000)	(7,000,000)
Equipment Revenue \| Sirius XM
Segment Reporting Information [Line Items]
Revenue	41,000,000
Equipment Revenue \| Pandora
Segment Reporting Information [Line Items]
Revenue	0
Other revenue
Segment Reporting Information [Line Items]
Revenue	36,000,000	$ 40,000,000
Other revenue \| Sirius XM
Segment Reporting Information [Line Items]
Revenue	36,000,000
Other revenue \| Pandora
Segment Reporting Information [Line Items]
Revenue	$ 0

The aggregate cost of services rendered during the reporting period, excluding depreciation, depletion and amortization.

No definition available.

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- Definition

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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