Commitments - Additional Information (Details) - USD ($) $ in Millions	Jul. 26, 2019	Jun. 30, 2019
Unrecorded Unconditional Purchase Obligation [Line Items]
Mozambique LNG project, additional obligations		$ 7,561
Mozambique LNG Project [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Mozambique LNG project, additional obligations		2,000
Mozambique LNG Project [Member] | Anadarko Excluding Wes [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Mozambique LNG project, additional obligations		$ 507
Mozambique LNG Project [Member] | Subsequent Event [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Mozambique LNG project, additional obligations	$ 8,000
Mozambique LNG Project [Member] | Subsequent Event [Member] | Anadarko Excluding Wes [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Mozambique LNG project, additional obligations	$ 2,100