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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-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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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

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

+ References

No definition available.

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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=49170532&loc=d3e12317-112629

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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-Name Accounting Standards Codification
-Topic 470
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Debt - Senior Notes (Details) - USD ($)		3 Months Ended		9 Months Ended
Debt - Senior Notes (Details) - USD ($)	Apr. 18, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015	Feb. 10, 2011
Debt Instrument [Line Items]
Loss on extinguishment of debt		$ 0	$ 0	$ 15,885,000	$ 0
6.00% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Face amount	$ 350,000,000
Debt issuance cost	6,000,000
Interest rate		6.00%		6.00%		6.00%
5.875% Senior Notes, Due 2024 \| Senior Notes
Debt Instrument [Line Items]
Interest rate		5.875%		5.875%		5.875%
5.125% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate		5.125%		5.125%		5.125%
5.875% Senior Notes, due 2022 \| Senior Notes
Debt Instrument [Line Items]
Interest rate		5.875%		5.875%		5.875%
6.625% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Face amount							$ 300,000,000
Interest rate		6.625%		6.625%		6.625%
Repurchase amount	231,000,000
Loss on extinguishment of debt	$ 15,900,000