Corporate Debt (Tables)

12 Months Ended

Dec. 31, 2017

Debt Disclosure [Abstract]

Schedule of Corporate Debt Instruments

Corporate debt at December 31, 2017 and 2016 is outlined in the following table (dollars in millions):

	Face Value		Discount			Net
December 31, 2017
Interest-bearing notes:
2.95% Notes, due 2022	$	600	$	(5	)	$	595
3.80% Notes, due 2027	400		(4		)	396
Total corporate debt	$	1,000	$	(9	)	$	991

December 31, 2016
Interest-bearing notes:
5.375% Notes, due 2022	$	540	$	(5	)	$	535
4.625% Notes, due 2023	460		(4		)	456
Total interest-bearing notes	1,000		(9		)	991
Non-interest-bearing debt:
0% Convertible debentures, due 2019	3		—			3
Total corporate debt	$	1,003	$	(9	)	$	994