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Condensed Consolidating Financial Information (Narrative) (Details) - USD ($)	Sep. 30, 2016	Apr. 21, 2015	Aug. 18, 2014
Senior Notes
Condensed Financial Statements, Captions [Line Items]
Debt instrument, amount			$ 600,000,000
Stated interest rate, percent			7.75%
Guarantors
Condensed Financial Statements, Captions [Line Items]
Ownership percentage by parent	100.00%
Notes Due 2023 | Senior Notes
Condensed Financial Statements, Captions [Line Items]
Debt instrument, amount		$ 350,000,000.0
Stated interest rate, percent		6.625%

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- Definition

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

+ References

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
-Publisher FASB
-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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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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