Pension and Postretirement Expense Level 4 (Details) - U.S. Pension Plan Investments Measured at Fair Value - Pension Plan [Member] - USD ($) $ in Millions	Dec. 31, 2019	Jul. 01, 2019	Dec. 31, 2018
UNITED STATES
Large Cap Equity Funds	$ 37		$ 33
Small mid Cap Equity Funds	6		5
Other International Equity	27		22
Debt Securities Fixed Income	103		102
Cash, Money Market and Other	2		3
Pension Benefits Fair Value of Plan Assets of Underfunded Plans	197	$ 196	185
Fair value of plan assets at end of year subtotal	175		165
Other funds	22		20
UNITED STATES | Fair Value, Inputs, Level 1 [Member]
Large Cap Equity Funds	0		0
Small mid Cap Equity Funds	0		0
Other International Equity	0		0
Debt Securities Fixed Income	0		0
Cash, Money Market and Other	0		0
Pension Benefits Fair Value of Plan Assets of Underfunded Plans	0		0
UNITED STATES | Fair Value, Inputs, Level 2 [Member]
Large Cap Equity Funds	37		33
Small mid Cap Equity Funds	6		5
Other International Equity	27		22
Debt Securities Fixed Income	103		102
Cash, Money Market and Other	2		3
Pension Benefits Fair Value of Plan Assets of Underfunded Plans	175		165
UNITED STATES | Fair Value, Inputs, Level 3 [Member]
Large Cap Equity Funds	0		0
Small mid Cap Equity Funds	0		0
Other International Equity	0		0
Debt Securities Fixed Income	0		0
Cash, Money Market and Other	0		0
Pension Benefits Fair Value of Plan Assets of Underfunded Plans	0		0
Foreign Plan [Member]
Cash, Money Market and Other	1		0
Pension Benefits Fair Value of Plan Assets of Underfunded Plans	13	$ 13	12
Fair value of plan assets at end of year subtotal	14		12
Foreign Plan [Member] | Fair Value, Inputs, Level 1 [Member]
Cash, Money Market and Other	0		0
Foreign Plan [Member] | Fair Value, Inputs, Level 2 [Member]
Cash, Money Market and Other	1		0
Foreign Plan [Member] | Fair Value, Inputs, Level 3 [Member]
Cash, Money Market and Other	$ 0		$ 0