The annual rate paid for the use of letters of credit.

No definition available.

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- Definition

Line of credit facility, aggregate maximum borrowing capacity after accordion feature adjustment.

+ References

No definition available.

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- Definition

Proceeds used to repay unsecured debt principal

+ References

No definition available.

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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

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 470
-Section 50
-Paragraph 3
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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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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

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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.

+ References

+ Details

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Debt (Narrative) (Details) - USD ($)			3 Months Ended		6 Months Ended
Debt (Narrative) (Details) - USD ($)	Feb. 15, 2018	Dec. 11, 2017	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Debt instrument, redemption price percentage	101.438%
Loss on extinguishment of debt	$ 3,300,000		$ 0	$ 0	$ 0	$ 3,339,000
Minimum
Debt Instrument [Line Items]
Letter of credit, fee percentage					1.50%
Maximum
Debt Instrument [Line Items]
Letter of credit, fee percentage					3.00%
Amended Facility \| Accordion Feature
Debt Instrument [Line Items]
Line of credit facility aggregate maximum borrowing capacity			2,000,000,000.0		$ 2,000,000,000.0
Senior Secured Credit Facility
Debt Instrument [Line Items]
Line of credit, unused capacity commitment fee percentage					0.50%
Credit facility, amount outstanding			967,000,000.0		$ 967,000,000.0
Total amount available for borrowings under credit facility			731,900,000		731,900,000
Senior Secured Credit Facility \| Petroleum Products
Debt Instrument [Line Items]
Credit facility, amount outstanding			30,300,000		$ 30,300,000
Senior Secured Credit Facility \| Minimum
Debt Instrument [Line Items]
Line of credit, unused capacity commitment fee percentage					0.25%
Senior Secured Credit Facility \| Maximum
Debt Instrument [Line Items]
Line of credit, unused capacity commitment fee percentage					0.50%
Senior Secured Credit Facility \| Letters Of Credit
Debt Instrument [Line Items]
Letter of credit, fee percentage					2.75%
Letters of credit, outstanding amount			1,100,000		$ 1,100,000
Senior Secured Credit Facility \| Letters Of Credit \| Maximum
Debt Instrument [Line Items]
Letters of credit, outstanding amount			100,000,000.0		100,000,000.0
Senior Secured Credit Facility \| Amended Facility
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity			1,700,000,000		1,700,000,000
Senior Secured Credit Facility \| Amended Facility \| Accordion Feature
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity			300,000,000.0		$ 300,000,000.0
Federal Funds Effective Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					0.50%
Federal Funds Effective Rate \| Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					1.00%
LIBOR Rate \| Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					1.00%
Eurodollar Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					2.75%
Eurodollar Rate \| Minimum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					1.50%
Eurodollar Rate \| Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					3.00%
Alternate Base Rate \| Minimum
Debt Instrument [Line Items]
Letter of credit, fee percentage					0.50%
Alternate Base Rate \| Maximum
Debt Instrument [Line Items]
Letter of credit, fee percentage					2.00%
Applicable Margin
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					1.75%
6.250% senior unsecured notes
Debt Instrument [Line Items]
Debt issued		$ 450,000,000	$ 450,000,000		$ 450,000,000		$ 450,000,000
Senior unsecured notes, stated rate		6.25%	6.25%		6.25%		6.25%
Proceeds from issuance of unsecured debt		$ 441,800,000
2021 Notes
Debt Instrument [Line Items]
Proceeds used to repay unsecured debt principal		$ 204,800,000