Contractual interest expense

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- Definition

Debt Instrument, Outstanding Principal

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No definition available.

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- Definition

Interest Expense, Adequate Protection Payments

+ References

No definition available.

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- Definition

Interest Expense, Stayed Amount

+ References

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
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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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- 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

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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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Long-term Debt Textuals (Details) - USD ($) $ in Millions	3 Months Ended
Long-term Debt Textuals (Details) - USD ($) $ in Millions	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Apr. 15, 2016	Apr. 13, 2016
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount	$ 167.2
Contractual interest expense	92.9
Interest expense	32.9	$ 126.2
Interest Expense, Adequate Protection Payments	29.8
Interest Expense, Stayed Amount	92.9
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt	1,555.2	$ 947.0	$ 1,558.1
Line of Credit Facility, Maximum Borrowing Capacity			1,650.0
Letters of Credit Outstanding, Amount					$ 675.0
2013 Term Loan Facility due September 2020 [Member]
Debt Instrument [Line Items]
Long-term debt	1,154.5		1,154.5
Debt Instrument, Outstanding Principal			1,170.0
6.00% Senior Notes due November 2018 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 1,509.9		1,509.9
Debt Instrument, Outstanding Principal			$ 1,518.8
Stated interest rate - percentage	6.00%		6.00%
6.50% Senior Notes due September 2020 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 645.8		$ 645.8
Debt Instrument, Outstanding Principal			$ 650.0
Stated interest rate - percentage	6.50%		6.50%
6.25% Senior Notes due November 2021 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 1,327.7		$ 1,327.7
Debt Instrument, Outstanding Principal			$ 1,339.6
Stated interest rate - percentage	6.25%		6.25%
10.00% Senior Secured Second Lien Notes Due 2022 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 962.3		$ 962.3
Debt Instrument, Outstanding Principal			$ 1,000.0
Stated interest rate - percentage			10.00%
7.875% Senior Notes due November 2026 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 245.9		$ 245.9
Debt Instrument, Outstanding Principal			$ 250.0
Stated interest rate - percentage	7.875%		7.875%
Convertible Junior Subordinated Debentures due December 2066 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 367.1		$ 367.1
Debt Instrument, Outstanding Principal			$ 732.5
DIP Facility - Initially Available [Member]
Debt Instrument [Line Items]
Long-term debt				$ 200.0
DIP Term Loan Facility [Member]
Debt Instrument [Line Items]
Debt Issuance Cost	$ 25.6