Debt Instrument, Redemption, Term

No definition available.

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- Definition

Ownership percentage, guarantor

+ References

No definition available.

+ Details

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- Definition

Percentage of minimum outstanding principal amount.

+ References

No definition available.

+ Details

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- Definition

Redemption Percentage, Maximum.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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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Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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Balance Type:	na
Period Type:	duration

- Definition

The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 944
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

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-Section S99
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- Details

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- Details

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- Details

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- Details

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Long-Term Debt - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Feb. 23, 2016	Feb. 22, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Ownership percentage, guarantors (as percent)			100.00%
Repurchase of senior unsecured debt			$ 56,925,000	$ 0
Gain on extinguishment of debt	$ 11,642,000	$ 0	18,658,000	0
Deferred financing costs	36,700,000		36,700,000
Interest Expense [Member]
Debt Instrument [Line Items]
Amortization of deferred financing costs	2,000,000	1,900,000	4,100,000	3,500,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Write-off of deferred financing costs		0
Line of Credit [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility amount	2,500,000,000		2,500,000,000
Line of credit facility, current borrowing capacity					$ 1,150,000,000.0	$ 1,525,000,000.0
Line of credit facility, amount outstanding	35,000,000		35,000,000
Outstanding letters of credit	14,200,000		14,200,000
Line of credit facility, remaining borrowing capacity	$ 1,100,800,000		$ 1,100,800,000
Weighted average interest rate (as percent)	2.00%		2.00%				1.90%
Commitment fee percentage			0.375%
Write-off of deferred financing costs	$ 0		$ 1,800,000	500,000
Line of Credit [Member] \| Revolving Credit Facility [Member] \| Other Assets [Member]
Debt Instrument [Line Items]
Deferred financing costs	5,700,000		5,700,000
Line of Credit [Member] \| Revolving Credit Facility [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Line of credit facility, amount outstanding	$ 35,000,000		$ 35,000,000
Senior Unsecured Debt [Member]
Debt Instrument [Line Items]
Redemption percentage (up to) (as percent)			35.00%
Redemption term			180 days
Percentage of minimum outstanding principal amount (at least)			65.00%
Senior Unsecured Debt [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Stated interest rate (as percent)	6.50%		6.50%
Senior Unsecured Debt [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Stated interest rate (as percent)	7.25%		7.25%
Senior Unsecured Debt [Member] \| Notes [Member]
Debt Instrument [Line Items]
Unsecured debt	$ 2,123,400,000		$ 2,123,400,000
Senior Unsecured Debt [Member] \| Notes [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Deferred financing costs	$ 31,000,000		$ 31,000,000
Senior Unsecured Debt [Member] \| 7.25% senior unsecured notes due February 1, 2019 [Member]
Debt Instrument [Line Items]
Stated interest rate (as percent)	7.25%		7.25%
Amount of debt extinguished			$ 1,000,000
Senior Unsecured Debt [Member] \| 6.5% senior unsecured notes due November 1, 2021 [Member]
Debt Instrument [Line Items]
Stated interest rate (as percent)	6.50%		6.50%
Amount of debt extinguished			$ 2,300,000
Senior Unsecured Debt [Member] \| 6.875% senior unsecured notes due March 15, 2022 [Member]
Debt Instrument [Line Items]
Stated interest rate (as percent)	6.875%		6.875%
Amount of debt extinguished			$ 59,500,000
Senior Unsecured Debt [Member] \| 6.875% senior unsecured notes due January 15, 2023 [Member]
Debt Instrument [Line Items]
Stated interest rate (as percent)	6.875%		6.875%
Amount of debt extinguished			$ 13,800,000
Senior Unsecured Debt [Member] \| Purchased Notes [Member]
Debt Instrument [Line Items]
Amount of debt extinguished			76,600,000
Repurchase of senior unsecured debt			56,900,000
Gain on extinguishment of debt	$ 11,600,000		18,700,000
Senior Unsecured Debt [Member] \| Purchased Notes [Member] \| Gain of Extinguishment of Debt [Member]
Debt Instrument [Line Items]
Write-off of deferred financing costs	$ 500,000	$ 0	$ 1,000,000	$ 0