Other Noncurrent Assets - Other Noncurrent Assets (Detail) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Other noncurrent assets:
Land held for development	$ 124.2	$ 129.2
Operating lease right-of-use assets	30.1
Restricted cash and cash equivalents	32.8	8.9
Land contract receivables	1.6	9.1
IBNR receivables	7.0	6.0
Marketable securities	6.5	4.8
Pension asset	3.2	2.7
Notes receivable - OPA	9.2	1.9
Other	11.7	12.7
Total	$ 226.3	$ 175.3

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