Fair Value Measurements (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2018

Dec. 31, 2017

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis

The following table presents the fair value hierarchy for those assets and liabilities measured at fair value on a recurring basis as of March 31, 2018 and December 31, 2017, respectively:



	March 31, 2018
	Level 1		Level 2		Level 3		Total
	(In millions)
Fixed maturity securities available for sale:
U.S. government and agencies	$	—	$	245	$	—	$	245
State and political subdivisions	—		230		—		230
Corporate debt securities	—		1,183		13		1,196
Mortgage-backed/asset-backed securities	—		53		—		53
Foreign government bonds	—		58		—		58
Preferred securities	23		293		—		316
Equity securities	677		—		—		677
Other long-term investments	—		—		101		101
Total assets	$	700	$	2,062	$	114	$	2,876



	December 31, 2017
	Level 1		Level 2		Level 3		Total
	(In millions)
Fixed maturity securities available for sale:
U.S. government and agencies	$	—	$	195	$	—	$	195
State and political subdivisions	—		391		—		391
Corporate debt securities	—		1,117		—		1,117
Mortgage-backed/asset-backed securities	—		56		—		56
Foreign government bonds	—		57		—		57
Preferred securities	23		296		—		319
Equity securities	681		—		—		681
Total assets	$	704	$	2,112	$	—	$	2,816

The following table presents our fair value hierarchy for those assets measured at fair value on a recurring basis as of December 31, 2017 and 2016, respectively:



	December 31, 2017
	Level 1		Level 2		Level 3		Total
	(In millions)
Assets:
Fixed-maturity securities available for sale:
U.S. government and agencies	$	—	$	195	$	—	$	195
State and political subdivisions	—		391		—		391
Corporate debt securities	—		1,117		—		1,117
Foreign government bonds	—		57		—		57
Mortgage-backed/asset-backed securities	—		56		—		56
Preferred stock available for sale	23		296		—		319
Equity securities available for sale	681		—		—		681
Total	$	704	$	2,112	$	—	$	2,816



	December 31, 2016
	Level 1		Level 2		Level 3		Total
	(In millions)
Fixed-maturity securities available for sale:
U.S. government and agencies	$	—	$	117	$	—	$	117
State and political subdivisions	—		615		—		615
Corporate debt securities	—		1,508		—		1,508
Foreign government bonds	—		109		—		109
Mortgage-backed/asset-backed securities	—		58		—		58
Preferred stock available for sale	32		283		—		315
Equity securities available for sale	386		—		—		386
Total	$	418	$	2,690	$	—	$	3,108