Additional collateral for debt

No definition available.

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- Definition

Debt Instrument, Covenant, Leverage Ratio

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant, Leverage Ratio, Certain Acquisitions

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant, Leverage Ratio, Certain Acquisitions Threshold

+ References

No definition available.

+ Details

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- Definition

Maximum the facility can be increased, subject to certain conditions.

+ References

No definition available.

+ Details

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- Definition

Number of dealer operated sites.

+ 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.

+ Details

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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.

+ Details

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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

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ 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.

+ References

+ Details

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- 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 carrying value as of the balance sheet date of the noncurrent portion 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=28361426&loc=d3e1314-112600

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=28361426&loc=d3e1336-112600

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Line-of-Credit Arrangement
-URI http://asc.fasb.org/extlink&oid=6517033

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- Details

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Long-Term Debt (Revolving Credit Agreement) (Details)			3 Months Ended
Long-Term Debt (Revolving Credit Agreement) (Details)	Mar. 31, 2016 USD ($)	Sep. 25, 2014 USD ($)	Sep. 30, 2016	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Apr. 10, 2015 USD ($)	Apr. 04, 2013 dealer
Debt Instrument [Line Items]
Revolving line of credit										$ 761,000,000	$ 1,000,000,000
Number Of Dealer Operated Sites \| dealer													50
2014 Revolver [Member]
Debt Instrument [Line Items]
Revolving line of credit										761,000,000	$ 1,000,000,000
Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Covenant, Leverage Ratio, Certain Acquisitions Threshold												$ 50,000,000
Revolving Credit Agreement [Member] \| Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			2.75%
Revolving Credit Agreement [Member] \| Minimum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			1.75%
Revolving Credit Agreement [Member] \| Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			3.00%
Revolving Credit Agreement [Member] \| Maximum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			2.00%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 1,250,000,000										1,500,000,000
Line of Credit Facility, Additional Borrowing Capacity												$ 250,000,000
Debt Instrument, Additional Collateral For Debt		66.00%
Revolving line of credit										761,000,000
Letters of Credit Outstanding, Amount										21,000,000
Current borrowing capacity										$ 718,000,000
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| Incremental Addition to One Month LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		1.00%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| Incremental Addition to Federal Funds Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		0.50%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Commitment fee percentage		0.25%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| Minimum [Member] \| Applicable Margin on LIBOR Loan [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		1.50%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| Minimum [Member] \| Applicable Margin on Base Rate Loan [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		0.50%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Commitment fee percentage		0.50%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| Maximum [Member] \| Applicable Margin on LIBOR Loan [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		3.00%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| Maximum [Member] \| Applicable Margin on Base Rate Loan [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		2.00%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| External Credit Rating, Investment Grade [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		0.125%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| External Credit Rating, Investment Grade [Member] \| Minimum [Member] \| Applicable Margin on LIBOR Loan [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		1.125%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| External Credit Rating, Investment Grade [Member] \| Minimum [Member] \| Applicable Margin on Base Rate Loan [Member]
Debt Instrument [Line Items]
Commitment fee percentage		0.125%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| External Credit Rating, Investment Grade [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		1.00%
Commitment fee percentage		0.275%
Revolving Credit Agreement [Member] \| 2014 Revolver [Member] \| External Credit Rating, Investment Grade [Member] \| Maximum [Member] \| Applicable Margin on LIBOR Loan [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		2.00%
Revolving Credit Agreement [Member] \| Scenario, Forecast [Member]
Debt Instrument [Line Items]
Debt Instrument, Covenant, Leverage Ratio				5.5	5.75	6.0	6.25	6.5	6.75
Debt Instrument, Covenant, Leverage Ratio, Certain Acquisitions				6.0
Medium-term Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Covenant, Leverage Ratio, Certain Acquisitions Threshold	$ 50,000,000
Medium-term Notes [Member] \| Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.50%		2.75%
Medium-term Notes [Member] \| Minimum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%		1.75%
Medium-term Notes [Member] \| Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%		3.00%
Medium-term Notes [Member] \| Maximum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%		2.00%
Medium-term Notes [Member] \| Scenario, Forecast [Member]
Debt Instrument [Line Items]
Debt Instrument, Covenant, Leverage Ratio				5.5	5.75	6.0	6.25	6.5	6.75
Debt Instrument, Covenant, Leverage Ratio, Certain Acquisitions				6.0