Credit Exposure Related to Coal Trading Activities

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- Definition

Potential collateralization that may be requested by counterparties due to a material adverse event.

+ References

No definition available.

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

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-Name Accounting Standards Codification
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- Definition

Cap rate on a foreign currency derivative for example, but not limited to, a cap or a collar.

+ References

No definition available.

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- Definition

The net amount as of the balance sheet date of the fair value of derivative assets and derivative liabilities that in accordance with the entity's accounting policy were offset against collateral under a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Nominal number of units used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

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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 transfers of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset) into (out of) level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Topic 820
-SubTopic 10
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-Paragraph 3
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- Definition

Amount receivable from broker-dealers and clearing organizations, including, but not limited to, securities failed-to-deliver, certain deposits for securities borrowed, open transactions, good faith and margin deposits, commissions and floor brokerage receivables.

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Derivatives and Fair Value Measurements - Textuals (Details) T in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019 USD ($) T	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) T	Sep. 30, 2018 USD ($)	Dec. 31, 2020 T	Jun. 30, 2020 $ / $	Dec. 31, 2019 T	Sep. 30, 2019 AUD ($) T	Dec. 31, 2018 USD ($)
Derivatives, Fair Value [Line Items]
Transfers between fair value levels 1, 2, and 3	$ 0	$ 0	$ 0	$ 0
Foreign currency option contracts
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount								$ 925,000,000.0
Coal
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount \| T	2.8		2.8					2.8
Diesel Fuel Hedge Contracts
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount								$ 0
Scenario, Forecast \| Coal
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount \| T					1.6		0.9
Scenario, Forecast \| Minimum \| Foreign currency option contracts
Derivatives, Fair Value [Line Items]
Derivative, exchange rate cap \| $ / $						0.73
Scenario, Forecast \| Maximum \| Foreign currency option contracts
Derivatives, Fair Value [Line Items]
Derivative, exchange rate cap \| $ / $						0.76
Coal Trading
Derivatives, Fair Value [Line Items]
Derivative, initial margin posted	$ 12,800,000		$ 12,800,000						$ 16,700,000
Derivatives, amount posted in excess of initial margin requirements	200,000		200,000						2,200,000
Derivative, variation margin	30,000,000.0		30,000,000.0						21,800,000
Potential collateralization that may be requested by counterparties due to a material adverse event	$ 100,000		$ 100,000						$ 1,300,000
Coal Trading Positions [Member] \| External Credit Rating, Investment Grade [Member] \| Coal Trading \| Credit Concentration Risk [Member]
Derivatives, Fair Value [Line Items]
Credit exposure related to Coal Trading activities	57.00%		57.00%					57.00%
Coal Trading Positions [Member] \| Non Rated [Member] \| Coal Trading \| Credit Concentration Risk [Member]
Derivatives, Fair Value [Line Items]
Credit exposure related to Coal Trading activities	43.00%		43.00%					43.00%