Under the credit facility, the interest coverage ratio as defined must exceed this specified level.

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Under the credit facility, the leverage ratio as defined cannot exceed this specified level.

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Under the credit facility, the senior secured leverage ratio as defined cannot exceed this specified level.

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Issue price of the notes as a percent of face value.

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

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Maximum percentage of the unsecured notes that can be redeem early prior to the specified date.

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No definition available.

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Principal amount of senior unsecured note that was tendered

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No definition available.

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The redemption premium for notes repaid up to a specified percentage of the total notes outstanding prior to the specified date.

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No definition available.

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- Definition

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

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No definition available.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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

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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.

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No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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.

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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.

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

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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.

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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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No definition available.

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The excess of the (1) fair value of consideration transferred to the holders of a security in excess of (2) the carrying amount of the security reported on the registrant's balance sheet, which will be deducted from net earnings to derive net earnings available to common shareholders. This amount is generally an adjustment considered in the computation of earnings per share.

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No definition available.

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Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Debt (Narrative) (Details)		3 Months Ended	9 Months Ended	12 Months Ended
Debt (Narrative) (Details)	Jul. 23, 2015 USD ($)	Jun. 30, 2015 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	May. 15, 2014 USD ($)	Feb. 08, 2013 USD ($)	Feb. 01, 2012 USD ($)
Debt Instrument [Line Items]
Commitment fee percentage				0.375%
Redemption Premium		$ 49,900,000
Gains (Losses) on Extinguishment of Debt		(19,225,000)		$ (19,225,000)	$ 0	$ 0
SENIOR UNSECURED NOTES, net of debt issuance costs				$ 1,807,054,000	1,030,889,000
Note Tender Offer		$ 300,100,000
Letter Of Credit [Member]
Debt Instrument [Line Items]
Letter of credit, fee percentage				2.50%
Senior Secured Credit Facility [Member]
Debt Instrument [Line Items]
Senior secured credit facility, amount outstanding				$ 1,100,000,000
Total amount available for borrowings, remaining borrowing capacity				374,300,000
Senior Secured Credit Facility [Member] \| Letter Of Credit [Member]
Debt Instrument [Line Items]
Letters of credit, outstanding amount				$ 10,700,000
Maturity date of debt				Jul. 28, 2019
Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt instrument, principal amount									$ 350,000,000
Debt instrument, percentage of face value									101.00%
Debt instrument, effective interest rate									7.682%
Six Percentage Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt instrument, principal amount				$ 400,000,000	0
SENIOR UNSECURED NOTES, net of debt issuance costs			$ 400,000,000	$ 392,175,000	0
Debt instrument, stated rate				6.00%
Percentage of the redeemable value of debt on Face amount				106.00%
Seven Point Eight Seventy Five Percentage Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt instrument, principal amount				$ 0	350,000,000				$ 100,000,000
SENIOR UNSECURED NOTES, net of debt issuance costs				$ 0	345,498,000
Debt instrument, stated rate				7.875%
Six Point Seven Five Percentage Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt instrument, principal amount	$ 750,000,000			$ 750,000,000	0
SENIOR UNSECURED NOTES, net of debt issuance costs				$ 727,572,000	0
Debt instrument, stated rate				6.75%
Proceeds from Debt, Net of Issuance Costs	$ 728,600,000
Percentage of the redeemable value of debt on Face amount				106.75%
Federal Funds Effective Rate [Member]
Debt Instrument [Line Items]
Interest rate spreads senior secured credit facility				0.50%
Eurodollar Rate [Member]
Debt Instrument [Line Items]
Interest rate spreads senior secured credit facility				2.50%
Applicable Margin [Member]
Debt Instrument [Line Items]
Interest rate spreads senior secured credit facility				1.50%
Five Point Seventy Five Percentage Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Maturity date of debt				Feb. 15, 2021
Debt instrument, principal amount				$ 350,000,000	350,000,000			$ 350,000,000
SENIOR UNSECURED NOTES, net of debt issuance costs				$ 344,817,000	343,798,000
Debt instrument, stated rate								5.75%
Five Point Six Two Five Percentage Senior Unsecured Notes [Member] [Domain]
Debt Instrument [Line Items]
Maturity date of debt				Jun. 15, 2024
Debt instrument, principal amount				$ 350,000,000	350,000,000		$ 350,000,000
SENIOR UNSECURED NOTES, net of debt issuance costs				$ 342,490,000	$ 341,593,000
Debt instrument, stated rate							5.625%
Maximum percentage of principal, early debt redemption			35.00%
Percentage of the redeemable value of debt on Face amount				105.625%
Maximum [Member]
Debt Instrument [Line Items]
Commitment fee percentage				0.375%
Maximum [Member] \| Senior Secured Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument covenant, requirement leverage ratio				1.00
Debt instrument covenant, requirement senior secured leverage ratio				1.00
Debt instrument covenant, requirement interest coverage ratio				1.00
Maximum [Member] \| Senior Secured Credit Facility [Member] \| Letter Of Credit [Member]
Debt Instrument [Line Items]
Letters of credit, outstanding amount				$ 100,000,000
Maximum [Member] \| Senior Secured Credit Facility [Member] \| Accordion [Member]
Debt Instrument [Line Items]
Senior secured credit facility, maximum borrowing capacity				$ 200,000,000
Maximum [Member] \| Federal Funds Effective Rate [Member]
Debt Instrument [Line Items]
Interest rate spreads senior secured credit facility				1.00%
Maximum [Member] \| LIBOR Rate [Member]
Debt Instrument [Line Items]
Interest rate spreads senior secured credit facility				1.00%
Maximum [Member] \| Eurodollar Rate [Member]
Debt Instrument [Line Items]
Letter of credit, fee percentage				2.50%
Maximum [Member] \| Alternate Base Rate [Member]
Debt Instrument [Line Items]
Letter of credit, fee percentage				1.50%
Minimum [Member]
Debt Instrument [Line Items]
Commitment fee percentage				0.25%
Minimum [Member] \| Senior Secured Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument covenant, requirement leverage ratio				5.00
Debt instrument covenant, requirement senior secured leverage ratio				3.75
Debt instrument covenant, requirement interest coverage ratio				3.00
Minimum [Member] \| Senior Secured Credit Facility [Member] \| Accordion [Member]
Debt Instrument [Line Items]
Senior secured credit facility, maximum borrowing capacity				$ 150,000,000
Minimum [Member] \| Eurodollar Rate [Member]
Debt Instrument [Line Items]
Letter of credit, fee percentage				1.50%
Minimum [Member] \| Alternate Base Rate [Member]
Debt Instrument [Line Items]
Letter of credit, fee percentage				0.50%
Amended Facility [Member]
Debt Instrument [Line Items]
Senior secured credit facility, maximum borrowing capacity				$ 1,500,000,000
Petroleum Products [Member] \| Senior Secured Credit Facility [Member]
Debt Instrument [Line Items]
Senior secured credit facility, amount outstanding				$ 33,800,000
Acquisition Period \| Maximum [Member] \| Senior Secured Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument covenant, requirement leverage ratio				1.00
Debt instrument covenant, requirement senior secured leverage ratio				1.00
Debt instrument covenant, requirement interest coverage ratio				1.00
Acquisition Period \| Minimum [Member] \| Senior Secured Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument covenant, requirement leverage ratio				5.50
Debt instrument covenant, requirement senior secured leverage ratio				4.25
Debt instrument covenant, requirement interest coverage ratio				2.75