Other Assets (Tables)

6 Months Ended

Jun. 30, 2020

Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]

Other Assets

	December 31,		June 30,
	2019		2020
	(In millions)
Other noncurrent assets:
Land held for development	$	125.3	$	102.9
Operating lease right-of-use assets		29.0		26.7
Restricted cash and cash equivalents		33.0		33.5
IBNR receivables		8.5		8.1
Marketable securities		6.2		5.4
Pension asset		7.4		8.0
Note receivables - OPA		8.8		27.6
Other		11.9		7.4
Total	$	230.1	$	219.6