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v3.21.2

Derivative Instruments (Details) $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2021 USD ($) | Jun. 30, 2021 USD ($) BTU | Dec. 31, 2020 USD ($) BTU
Derivative [Line Items] |  |  |
Gain (loss) on derivatives | $ (3.3) | $ (2.8) |
Natural Gas | Commodity Contract | Not Designated as Hedging Instrument |  |  |
Derivative [Line Items] |  |  |
Derivative energy measure (in BTUs) | BTU |  | 4,000 | 0
Natural gas swap contracts, current asset |  |  | $ 0.0
Natural gas swap contracts, current liability | $ 2.5 | $ 2.5 | $ 0.0

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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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