Long-Term Debt - Schedule of Extinguished Portion of Certain Series of Outstanding Notes (Details) $ in Millions	3 Months Ended
	Sep. 30, 2020 USD ($)
Debt Instrument [Line Items]
Total principal amount of debt extinguished	$ 261
Senior Notes | 6.875% Senior Notes due 2028
Debt Instrument [Line Items]
Total principal amount of debt extinguished	226
Senior Notes | 6.875% Senior Notes due 2022
Debt Instrument [Line Items]
Total principal amount of debt extinguished	34
Junior-Priority Secured Notes | 8.125% Junior-Priority Secured Notes due 2024
Debt Instrument [Line Items]
Total principal amount of debt extinguished	$ 1