Cash Collateral Or Restricted Cash Requirement

No definition available.

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- Definition

Financial Instrument, Surety Bonds Amount

+ References

No definition available.

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- Definition

Financial Instrument, Surety Bonds Amount To Support Asset Retirement Obligations

+ References

No definition available.

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- Definition

Letters Of Credit Issued To Support Asset Retirement Obligations

+ References

No definition available.

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- Definition

Loss Contingency, Damage Sought, Irrevocable Letter Of Credit Amount

+ References

No definition available.

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- Definition

Loss Contingency, Damage Sought, Release Of Bonds

+ References

No definition available.

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- Definition

The amount owed to the reporting entity by counterparties in securitized loan transactions.

+ References

No definition available.

+ Details

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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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 the cost of borrowed funds accounted for as interest expense.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Financial Instruments and Other Guarantees (Details) $ in Millions	1 Months Ended			3 Months Ended		9 Months Ended
	Nov. 09, 2020 USD ($)	Nov. 09, 2020 AUD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Oct. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Guarantee Obligations [Line Items]
Surety bonds amount			$ 1,628,700,000	$ 1,628,700,000		$ 1,628,700,000
Letters of credit outstanding, amount			334,800,000	334,800,000		334,800,000
Asset retirement obligations			762,800,000	762,800,000		762,800,000
Surety bonds issued to support asset retirement obligations			1,439,800,000	1,439,800,000		1,439,800,000
Letters of credit issued to support asset retirement obligations			235,900,000	235,900,000		235,900,000
Accounts receivable securitization program availability			40,400,000	40,400,000		40,400,000			$ 45,000,000.0
Cash collateral or restricted cash requirement			0	0		0			0
Net interest expense				34,900,000	$ 35,400,000	102,300,000	$ 107,200,000
Subsequent Event
Guarantee Obligations [Line Items]
Loss contingency, release of bonds value sought	$ 202,900,000
Loss contingency, irrevocable letter of credit amount sought	$ 182,400,000
Loss contingency, payment amount sought		$ 48.3
Accounts receivable securitization program availability								$ 45,800,000
Accounts Receivable Securitization Program, April 1, 2022 \| Secured debt
Guarantee Obligations [Line Items]
Letters of credit outstanding, amount			3,400,000	3,400,000		3,400,000
Line of credit facility, maximum borrowing capacity			250,000,000.0	250,000,000.0		250,000,000.0
Outstanding borrowings			60,000,000.0	60,000,000.0		60,000,000.0
Accounts receivable securitization program availability			40,400,000	40,400,000		40,400,000
Collateral posted			$ 0	0		0			$ 0
Net interest expense				$ 800,000	$ 1,000,000.0	$ 2,900,000	$ 3,600,000
Accounts Receivable Securitization Program, April 1, 2022 \| Secured debt \| London Interbank Offered Rate (LIBOR)
Guarantee Obligations [Line Items]
Basis spread on variable rate			1.50%