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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Topic 835
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-Section 45
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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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

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- Definition

For an unclassified balance sheet, the amount as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain. Such amount is before the consideration of accumulated amortization.

+ 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

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
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12317-112629

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Debt - Senior Notes (Details) - USD ($)	1 Months Ended		12 Months Ended
Debt - Senior Notes (Details) - USD ($)	Nov. 30, 2014	Jun. 30, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Apr. 02, 2013
Debt Instrument [Line Items]
Loss on Modification or Extinguishment of Debt			$ 0	$ 14,400,000	$ 27,100,000
Senior Notes \| Senior Notes due in 2021
Debt Instrument [Line Items]
Principal amount						$ 425,000,000
Stated interest rate			4.80%	4.80%		4.75%
Deferred financing costs						$ 7,200,000
Senior Notes \| Senior Notes due in 2017
Debt Instrument [Line Items]
Principal amount		$ 425,000,000
Stated interest rate		9.50%
Percent of principal amount redeemed		100.00%
Redemption price		104.75%
Loss on Modification or Extinguishment of Debt		$ 25,900,000
Senior Notes \| Senior Notes due in 2022
Debt Instrument [Line Items]
Principal amount	$ 250,000,000
Stated interest rate	4.875%		4.95%	4.95%
Deferred financing costs	$ 4,400,000
Senior Notes \| Senior Notes due in 2018
Debt Instrument [Line Items]
Principal amount	$ 250,000,000.0
Stated interest rate	7.875%
Percent of principal amount redeemed	100.00%
Redemption price	103.94%
Loss on Modification or Extinguishment of Debt	$ 12,100,000