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- Definition

Equity Method Investment, Consideration Transferred, Equity Interests Issued and Issuable

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Equity Method Investment, Number of Preferred Shares Owned

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- Definition

Equity method investment, voting interest.

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- Definition

Notes Receivable, Related Parties, Annual Prepayment Excess Cash Threshold

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Notes Receivable, Related Parties, Annual Principal Repayment Period

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Notes Receivable, Related Parties, Maturity Period

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Number of related party members on the board of directors.

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Number of Shareholders

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Proceeds from Equity Method Investment, Distribution, Including Return of Capital

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Related Party Transaction, Payments Receivable, Percent of Gross Revenue

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Related Party Transaction, Period Of Agreement

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Related party transaction related party ownership percentage.

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- Definition

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

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amounts due from parties associated with the reporting entity as evidenced by a written promise to pay, due after 1 year (or 1 business cycle).

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

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The cash inflow from a long-term borrowing made from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from Advances from Affiliates.

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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.

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Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

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Number of shares of stock issued during the period as part of a transaction to acquire assets that do not qualify as a business combination.

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Related Party Transactions - Liberty Media, Sirius XM Canada - Additional Information (Details) $ / shares in Units, $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended		5 Months Ended	9 Months Ended		12 Months Ended
	May 25, 2017 USD ($)	Sep. 30, 2018 USD ($) director executive $ / shares shares	Sep. 30, 2017 USD ($)	May 24, 2017 shareholder	Sep. 30, 2018 USD ($) director executive $ / shares shares	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) shares	Sep. 30, 2018 $ / shares	Jan. 01, 2018 USD ($)	May 25, 2017 CAD ($)
Related Party Transaction [Line Items]
Preferred stock liquidation preference per share (in Canadian dollars per share) \| $ / shares		$ 0.001			$ 0.001
Current portion of deferred revenue		$ 1,921,517			$ 1,921,517		$ 1,881,825		$ 1,839,923
Deferred revenue, noncurrent		$ 154,145			$ 154,145		174,579		$ 170,589
Management \| Liberty Media \| Executives
Related Party Transaction [Line Items]
Number of related party members on the board of directors \| executive		2			2
Management \| Liberty Media \| Director
Related Party Transaction [Line Items]
Number of related party members on the board of directors \| director		1			1
Management \| Liberty Media \| Common Stock
Related Party Transaction [Line Items]
Related party ownership percentage		71.00%			71.00%
Equity Method Investee
Related Party Transaction [Line Items]
Notes receivable, related parties	$ 130,794
Notes receivable, maturity period	15 years
Interest rate	7.62%
Annual principal repayment period	60 days
Annual prepayment cash threshold										$ 10,000,000
Notes receivable, repayment from related party					$ 3,242
Current portion of deferred revenue		$ 2,776			2,776		2,776
Deferred revenue, noncurrent		$ 3,006			$ 3,006		$ 5,088
Equity Method Investee \| Services Agreement
Related Party Transaction [Line Items]
Period of agreement	30 years
Equity Method Investee \| Services Agreement, Years 1 Through 5
Related Party Transaction [Line Items]
Percent of gross revenue receivable	25.00%
Equity Method Investee \| Services Agreement, Years 6 Through 30
Related Party Transaction [Line Items]
Percent of gross revenue receivable	30.00%
Equity Method Investee \| Advisory Services Agreement
Related Party Transaction [Line Items]
Percent of gross revenue receivable	5.00%
Equity Method Investee \| Common Stock
Related Party Transaction [Line Items]
Issuance of common stock as part of recapitalization of Sirius XM Canada (in shares) \| shares							35,000
Equity Method Investee \| Sirius XM Canada
Related Party Transaction [Line Items]
Equity method investment, equity interest	70.00%									70.00%
Equity method investment, voting interest	33.00%									33.00%
Number of shareholders \| shareholder				2
Consideration transferred							$ 308,526
Payments to acquire equity method investments							129,676
Consideration transferred, equity interests issued and issuable							178,850
Number of preferred shares owned (in shares) \| shares		590,950			590,950
Preferred stock liquidation preference per share (in Canadian dollars per share) \| $ / shares								$ 1
Notes receivable, related parties		$ 133,157			$ 133,157		140,073
Equity method investments		331,231			331,231		$ 341,214
Equity method investment, dividends, including reduction of investment		$ 402	$ 0		$ 1,840	$ 3,796