Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2019

Fair Value Disclosures [Abstract]

Schedule of Fair Value of Investment Assets

The Company's investment assets are carried at fair value on the consolidated balance sheets as summarized in the following table. All of the inputs used to determine the fair value of the Company's investments are Level 2 inputs. The amortized cost basis of these investments was $957 million and $340 million as of June 30, 2019 and December 31, 2018, respectively.

(Dollars in Millions)	June 30, 2019		December 31, 2018
Certificates of Deposit and Commercial Paper	$	869	$	250
Corporate Bonds	61		56
Government Securities	34		35
Total investments at fair value	$	964	$	341

Schedule of Investment Maturities

These investments have the following maturities:

(Dollars in millions)	June 30, 2019		December 31, 2018
Less than 1 year	$	878	$	253
1 - 5 years	8		14
5 - 10 years	27		26
Greater than 10 years	51		48
Total investments at fair value	$	964	$	341

Schedule of Fair Value and Carrying Value of Long-Term Debt

The fair value and carrying value of the Company's long-term debt is as follows:

(Dollars in millions)	June 30, 2019		December 31, 2018
Long-term Debt (Including Current Maturities):
Fair Value	$	17,536	$	14,914
Carrying Value	15,767		14,757