Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2020

Investments Debt And Equity Securities [Abstract]

Schedule of Marketable Securities

	Market value		Cost basis		Unrealized gains (losses), net
	(In millions)
December 31, 2019:
Current assets	$	2.1	$	2.1	$	-
Noncurrent assets	$	6.2	$	6.2	$	-
December 31, 2020:
Current assets	$	4.4	$	4.4	$	-
Noncurrent assets	$	2.9	$	2.9	$	-

Schedule of Marketable Securities and Fair Value Measurements

	Fair Value Measurements
	Total		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)
	(In millions)
December 31, 2019:
Current assets	$	2.1	$	-	$	2.1
Noncurrent assets:
Fixed income securities	$	4.9	$	-	$	4.9
Common stocks and exchange traded funds		1.3		1.3		-
Total	$	6.2	$	1.3	$	4.9
December 31, 2020:
Current assets	$	4.4	$	-	$	4.4
Noncurrent assets:
Fixed income securities	$	2.7	$	-	$	2.7
Common stocks		.2		.2		-
Total	$	2.9	$	.2	$	2.7