Other Assets (Tables)

3 Months Ended

Mar. 31, 2021

Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]

Other Assets

	December 31,		March 31,
	2020		2021
	(In millions)
Other noncurrent assets:
Land held for development	$	96.0	$	80.5
Operating lease right-of-use assets		26.1		24.6
Restricted cash and cash equivalents		37.8		37.7
IBNR receivables		37.1		37.7
Marketable securities		2.9		2.8
Pension asset		8.4		8.5
Note receivables - OPA		25.3		30.1
Other		8.7		10.6
Total	$	242.3	$	232.5