Other Noncurrent Assets - Other Noncurrent Assets (Detail) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Other noncurrent assets:
Land held for development	$ 123.1	$ 126.6
Restricted cash	9.0	9.9
Land contract receivables	7.3
IBNR receivables	6.9	6.8
Pension asset	6.0	4.2
Notes receivable - OPA	2.6
Other	20.6	26.6
Total	$ 175.5	$ 174.1

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Amount, before allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as noncurrent.

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date(s) more than one year from the balance sheet date. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Land held for development noncurrent.

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