Defined Benefit Plan, Maximum Annual Employer Contributions, Amount

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for incentive compensation awarded to employees and directors or earned by them based on the terms of one or more relevant arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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- Definition

Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

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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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in remainder of current fiscal year. Excludes contribution previously paid by employer in current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of cash outflow for other postretirement benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes pension benefit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
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-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3536-108585

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Employee Benefits - Additional Information (Details) - USD ($)	3 Months Ended	6 Months Ended		12 Months Ended
	Mar. 31, 2021	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Payment for Other Postretirement Benefits		$ 1,700,000	$ 2,900,000
Warrick \| Accrued Salaries, Wages and Related Expenses
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	$ 1,100,000
Postretirement Health Coverage \| Salaried VEBA
Defined Benefit Plan Disclosure [Line Items]
Maximum contribution threshold				$ 2,900,000
Payment for Other Postretirement Benefits	1,700,000
Pension Plan \| Warrick
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	6,500,000
Expected minimum employer contributions in 2021	100,000
Other Postretirement Benefits Plan \| Warrick
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	78,100,000
Expected minimum employer contributions in 2021	$ 700,000
Level 2 \| Fair Value, Measurements, Recurring
Defined Benefit Plan Disclosure [Line Items]
Fair value of deferred compensation assets		10,300,000		$ 9,600,000
Accrued salaries, wages and related expenses
Defined Benefit Plan Disclosure [Line Items]
Accrued salaries, wages and related expenses		$ 6,700,000