Investments of Insurance Subsidiaries (Tables)

6 Months Ended

Jun. 30, 2018

Investments, Debt and Equity Securities [Abstract]

Schedule of Investments

A summary of our insurance subsidiaries’ investments at June 30, 2018 and December 31, 2017 follows (dollars in millions):

	June 30, 2018
	Amortized Cost		Unrealized Amounts					Fair Value
			Gains		Losses
Debt securities	$	337	$	5	$	(1	)	$	341
Money market funds and other		118		—		—			118
	$	455	$	5	$	(1	)		459
Amounts classified as current assets									(45	)
Investment carrying value								$	414

	December 31, 2017
	Amortized Cost		Unrealized Amounts				Fair Value
			Gains		Losses
Debt securities	$	361	$	10	$	—	$	371
Money market funds and other		101		—		—		101
	$	462	$	10	$	—		472
Amounts classified as current assets								(54	)
Investment carrying value							$	418

Schedule of Maturities of Investments

Scheduled maturities of investments in debt securities at June 30, 2018 were as follows (dollars in millions):

	Amortized Cost		Fair Value
Due in one year or less	$	24	$	25
Due after one year through five years		50		50
Due after five years through ten years		218		221
Due after ten years		45		45
	$	337	$	341