Fair Value Of Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2020

Fair Value Of Financial Instruments [Abstract]

Fair Value Of Long-Term Debt

	September 30, 2020				December 31, 2019
($ in millions)		Carrying Amount		Fair Value		Carrying Amount		Fair Value
Total debt	$	16,762	$	10,539	$	17,516	$	12,026