Commitments and Contingencies (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Carrying amount of liability for certain obligations of the settlement	$ 17.7
Remaining estimated maximum potential amount of monetary payments subject to guaranty	23.7
Outstanding performance bonds	218.2	$ 73.5
Outstanding letters of credit	2.4	2.4
Letter of Credit
Lessee, Lease, Description [Line Items]
Restricted cash and certificates of deposit pledged as collateral	1.4	$ 1.4
The San Francisco Venture
Lessee, Lease, Description [Line Items]
Guaranty of infrastructure obligations, maximum obligation	$ 197.8

Monetary Payments Subject to Guaranty, Remaining Estimated Amount, Maximum

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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-Publisher FASB
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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The carrying amount, as of the date of the latest financial statement presented, of other assets which are owned but transferred to serve as collateral for the payment of the related debt obligation, primarily a secured borrowing or repurchase agreement, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of a type of municipal bond typically used to fund a development project. Also called special assessment limited liability bond, special district bond, special purpose bond, special tax bond and community development obligation. Interest owed to lenders is paid by taxes levied on the community benefiting from the particular bond-funded project. For example, if a bond of this sort was issued to pay for sidewalks to be repaved in a certain community, an additional tax would be levied on homeowners in the area benefiting from this project.

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