Pension and Postretirement Expense Level 4 (Details) - Components of Net Pension and Non-pension postretirement Expense - USD ($) $ in Millions	6 Months Ended		12 Months Ended
	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Postretirement Benefits Plan [Member] | UNITED STATES
Pension Benefits and Non-Pension Postretirement Benefits Disclosures Table Text Block [Line Items]
Interest cost	$ 0	$ 0	$ 0	$ 0
Amortization of prior service cost	0	0	0	0
Unrealized actuarial loss (gain)(1)	0	0	0	(1)
Net expense (benefit)	0	0	0	(1)
Other Postretirement Benefits Plan [Member] | Foreign Plan [Member]
Pension Benefits and Non-Pension Postretirement Benefits Disclosures Table Text Block [Line Items]
Interest cost	0	0	1	1
Amortization of prior service cost	0	0	0	0
Unrealized actuarial loss (gain)(1)	(4)	4	2	1
Net expense (benefit)	(4)	4	3	2
Pension Plan [Member] | UNITED STATES
Pension Benefits and Non-Pension Postretirement Benefits Disclosures Table Text Block [Line Items]
Service cost	2	2	3	3
Interest cost	3	4	7	7
Expected return on assets	(7)	(6)	(14)	(13)
Amortization of prior service cost	0	0
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)			0	0
Unrealized actuarial loss (gain)(1)	0	1	11	(6)
Net expense (benefit)	(2)	1	7	(9)
Pension Plan [Member] | Foreign Plan [Member]
Pension Benefits and Non-Pension Postretirement Benefits Disclosures Table Text Block [Line Items]
Service cost	8	7	17	16
Interest cost	4	4	10	9
Expected return on assets	(6)	(6)	(13)	(11)
Amortization of prior service cost	0	0
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)			0	(1)
Unrealized actuarial loss (gain)(1)	9	39	(26)	1
Net expense (benefit)	$ 15	$ 44	$ (12)	$ 14