Commitments and Contingent Liabilities Environmental (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	$ 381	$ 433
Accrual for Environmental Loss Contingencies, Potential Exposure in Excess of Accrual	750
Superfund Sites [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	54	$ 67
Chemours [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	193
Accrual for Environmental Loss Contingencies, Potential Exposure in Excess of Accrual	310
Indemnification Agreement [Member] | Chemours [Member]
Loss Contingencies [Line Items]
Indemnification Assets	193
Indemnification Agreement [Member] | Chemours [Member] | Superfund Sites [Member]
Loss Contingencies [Line Items]
Indemnification Assets	$ 35