Estimated annual expenses related to PD Trust

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- Definition

Frequency of PD Trust Payments

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No definition available.

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- Definition

Represents the minimum amount of assets which is required to be maintained as a condition for payment of contingent obligation by the entity to the Trust.

+ References

No definition available.

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- Definition

Represents the number of shares issuable under the warrant as per the agreement.

+ References

No definition available.

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- Definition

Period in Which ZAI PD Contingent Deferred Payments Will be Made

+ References

No definition available.

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- Definition

Represents deferred payments amount per year payable for twenty years by the entity to the Trust.

+ References

No definition available.

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- Definition

ZAI PD Account Funding

+ References

No definition available.

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- Definition

ZAI PD Trust Balance

+ References

No definition available.

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- Definition

Represents the maximum number of contingent deferred payments to be provided by the entity to the Trust.

+ References

No definition available.

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- Definition

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

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- Definition

The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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- Definition

The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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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.

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No definition available.

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- Definition

Estimated time frame of disbursements over which the accrued or presently unrecognized amounts may be paid out for an individual site.

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Commitments and Contingent Liabilities (Details) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2019 USD ($) shares	Mar. 31, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) payment shares	Dec. 31, 2018 USD ($)	Feb. 03, 2017 USD ($)	Feb. 03, 2014 USD ($)
Other Commitments [Abstract]
ZAI PD account funding						$ 30.0	$ 34.4
ZAI P D account, maximum number of contingent deferred payments \| payment				10
ZAI P D account, deferred payments, each year for twenty years				$ 8.0
Period in which ZAI PD contingent deferred payments will be made				20 years
Minimum ZAI P D account assets for condition in relation to contingent obligation payments	$ 10.0			$ 10.0
ZAI PD Trust Balance					$ 30.0
Frequency of PD trust payments				6 months
Estimated annual expenses related to PD Trust				$ 0.2
Number of shares issuable under warrant (in shares) \| shares	77,372,257			77,372,257
Legacy Matters
Accrual for Environmental Loss Contingencies	$ 118.2			$ 118.2	126.4
Non-Vermiculite Related Matters
Legacy Matters
Accrual for Environmental Loss Contingencies	40.4			40.4	44.7
Vermiculite Related Matters
Legacy Matters
Accrual for Environmental Loss Contingencies	77.8			77.8	$ 81.7
Operable Unit 3 [Member]
Legacy Matters
Environmental Remediation Expense			$ 70.0
Spillway [Member]
Legacy Matters
Loss Contingency, Loss in Period		$ 45.0
Minimum \| Operable Unit 3 [Member]
Legacy Matters
Loss Contingency, Estimate of Possible Loss	30.0			30.0
Minimum \| Spillway [Member]
Legacy Matters
Loss Contingency, Estimate of Possible Loss	$ 25.0			25.0
Site Contingency, Time Frame of Disbursements	P3Y
Maximum \| Operable Unit 3 [Member]
Legacy Matters
Loss Contingency, Estimate of Possible Loss	$ 170.0			170.0
Maximum \| Spillway [Member]
Legacy Matters
Loss Contingency, Estimate of Possible Loss	$ 80.0			80.0
Site Contingency, Time Frame of Disbursements	P4Y
ZAI PD Trust [Member] \| Valuation Technique, Discounted Cash Flow [Member] \| Minimum
Legacy Matters
Loss Contingency, Estimate of Possible Loss	$ 0.0			0.0
ZAI PD Trust [Member] \| Valuation Technique, Discounted Cash Flow [Member] \| Maximum
Legacy Matters
Loss Contingency, Estimate of Possible Loss	$ 20.0			$ 20.0