Commitments and Contingencies Level 4 (Details) - Environmental Liabilities $ in Millions	6 Months Ended
Dec. 31, 2019 USD ($) sites	Dec. 31, 2018 USD ($)
Accrued Environmental Loss Contingencies, Current	$ 18	$ 11
Liability	$ 51	50
Number of Sites \| sites	45
Estimated Litigation Liability	$ 3	0
Geismar, LA [Member]
Discount rate assumed to record at present value	3.00%
Undiscounted Liability Expected to be Paid	20 years
Geismar, LA Site Contingency, Accrual, Undiscounted Amount	$ 16
Accrual for Environmental Loss Contingencies, Undiscounted, Due Ratably over the Next Five Years	5
Formerly-Owned - Remediation [Member]
Accrued Environmental Loss Contingencies, Current	10
Liability	21	22
Estimated Litigation Liability, Noncurrent	12
Superfund and Offsite Landfills - allocated share: Equal to or Greater than 1% [Member]
Liability	6	5
Superfund and Offsite Landfills - Less than 1% [Member]
Liability	3	3
Geismar, LA [Member]
Liability	12	13
Formerly-Owned - Monitoring Only [Member]
Liability	1	1
Currently-Owned [Member]
Liability	8	$ 6
Minimum [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	39
Minimum [Member] \| Formerly-Owned - Remediation [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	18
Minimum [Member] \| Superfund and Offsite Landfills - allocated share: Equal to or Greater than 1% [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	5
Minimum [Member] \| Superfund and Offsite Landfills - Less than 1% [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	2
Minimum [Member] \| Geismar, LA [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	9
Minimum [Member] \| Formerly-Owned - Monitoring Only [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	1
Minimum [Member] \| Currently-Owned [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	4
Maximum [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	97
Maximum [Member] \| Formerly-Owned - Remediation [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	40
Maximum [Member] \| Superfund and Offsite Landfills - allocated share: Equal to or Greater than 1% [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	14
Maximum [Member] \| Superfund and Offsite Landfills - Less than 1% [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	6
Maximum [Member] \| Geismar, LA [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	22
Maximum [Member] \| Formerly-Owned - Monitoring Only [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	1
Maximum [Member] \| Currently-Owned [Member]
Site Contingency, Loss Exposure Not Accrued, Best Estimate	$ 14

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