Liberty Media Corporation Quarterly report pursuant to Section 13 or 15(d)

Long-Term Debt - Fair Value of Debt (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, measured at fair value	$ 2,388	$ 2,115
Sirius XM 3.875% Senior Notes due 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, measured at fair value	980
Sirius X M 4.625 Senior Notes Due 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, measured at fair value	495
Sirius XM 6.00% Senior Notes Due 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, measured at fair value	1,552
Sirius XM 5.375% Senior Notes Due 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, measured at fair value	1,003
Sirius XM 5.375% Senior Notes due 2026
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, measured at fair value	993
Sirius XM 5.0% Senior Notes due 2027 Member
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, measured at fair value	$ 1,438