Redemption Price Percentage Of Principal Prior To November 15, 2016.

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- Definition

Repurchase Percentage Price Of Aggregate Principal Due To Change In Control

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- Definition

Unpaid Indebtedness After Maturity Or Acceleration

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- Definition

Unpaid Judgment Or Decree

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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=64930739&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=64930785&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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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.

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Debt and liquidity debt and liquidity (Senior Notes) (Details) - USD ($)	Dec. 31, 2017	Sep. 30, 2017	Nov. 20, 2012
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.375%
Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 300,000,000
Debt Instrument, Interest Rate, Stated Percentage	6.375%		6.375%
Redemption price percentage of principal prior to November 15, 2016			100.00%
Repurchase Percentage Price Of Aggregate Principal Due To Change In Control			101.00%
Minimum
Debt Instrument [Line Items]
Unpaid indebtedness after maturity or acceleration	$ 50,000,000
Unpaid judgment or decree	$ 50,000,000
Minimum \| Senior Notes
Debt Instrument [Line Items]
Unpaid judgment or decree		$ 50,000,000