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v3.21.2

Commitments and Contingencies - Additional Information (Detail) |  |  |  | 1 Months Ended | 6 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 17, 2017 Defendant | Mar. 04, 2016 USD ($) | Jul. 07, 2014 Defendant | May 31, 2007 Defendant | Jun. 30, 2018 Defendant | Dec. 31, 2004 Entity | Jun. 30, 2021 USD ($) | Dec. 31, 2020 USD ($) | Jan. 31, 2018 USD ($) Party | Mar. 30, 2017 Party
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Accrued legal matters | $ |  |  |  |  |  |  | $ 4,275,000 | $ 4,275,000 |  |
EPA [Member] | Occidental Chemical Corporation [Member] |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Number of potentially responsible parties | Party |  |  |  |  |  |  |  |  |  | 20
Number of potentially responsible parties that the EPA intends to enter into a final settlement agreement with | Party |  |  |  |  |  |  |  |  | 15 |
Remediation cost for identified responsible parties | $ |  |  |  |  |  |  |  |  | $ 280,600 |
8 Mile Stretch of Lower Passaic River [Member] |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Cost estimate for remediating Lower Passaic River | $ |  | $ 1,380,000,000 |  |  |  |  |  |  |  |
Minimum [Member] | CERCLA [Member] | Occidental Chemical Corporation [Member] |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Number of defendants under complaint |  |  |  |  | 120 |  |  |  |  |
Minimum [Member] | 17 Mile Stretch of Lower Passaic River [Member] | EPA [Member] |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Number of entities to which general notice letters issued | Entity |  |  |  |  |  | 100 |  |  |  |
Lower Passaic River [Member] | Minimum [Member] | 17 Mile Stretch of Lower Passaic River [Member] |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Parties to perform a remedial investigation and feasibility study |  |  |  | 70 |  |  |  |  |  |
MTBE [Member] | Minimum [Member] | PA [Member] |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Number of defendants in the MTBE complaint |  |  | 50 |  |  |  |  |  |  |
MTBE [Member] | Minimum [Member] | MARYLAND [Member] |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Number of defendants in the MTBE complaint | 60 |  |  |  |  |  |  |  |  |

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