Long Term Debt, Weighted Average Maturity

No definition available.

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- Definition

Number of Series

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- 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

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13476-108611

+ Details

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Balance Type:	credit
Period Type:	instant

- 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.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16(a))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Period Type:	instant

- Details

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- Details

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Senior Notes (Detail)	Jul. 14, 2010 USD ($) Contract	May 07, 2008 USD ($) Contract	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)
Debt Instrument [Line Items]
Senior Notes, weighted average interest rate			2.655%
Carrying value of Senior Notes			$ 243,834,000	$ 243,801,000
Fair value of Senior Notes			250,317,000	253,157,000
Debt issuance costs			(166,000)	(199,000)
May 2008 Senior Notes
Debt Instrument [Line Items]
Senior Notes issued in a private placement to a group of institutional investors		$ 275,000,000
Number of series of Senior Notes issued \| Contract		4
Senior Notes, weighted average interest rate		7.20%
Senior Notes, weighted average maturity (in years)		10 years
Carrying value of Senior Notes			131,000,000	131,000,000
Fair value of Senior Notes			132,814,000	134,250,000
May 2008 Senior Notes \| Minimum
Debt Instrument [Line Items]
Senior Notes, maturity (in years)		5 years
May 2008 Senior Notes \| Maximum
Debt Instrument [Line Items]
Senior Notes, maturity (in years)		10 years
July 2010 Senior Notes
Debt Instrument [Line Items]
Senior Notes issued in a private placement to a group of institutional investors	$ 245,000,000
Number of series of Senior Notes issued \| Contract	4
Senior Notes, weighted average interest rate	5.60%
Senior Notes, weighted average maturity (in years)	9 years 10 months
Carrying value of Senior Notes			113,000,000	113,000,000
Fair value of Senior Notes			$ 117,669,000	$ 119,106,000
July 2010 Senior Notes \| Minimum
Debt Instrument [Line Items]
Senior Notes, maturity (in years)	6 years
July 2010 Senior Notes \| Maximum
Debt Instrument [Line Items]
Senior Notes, maturity (in years)	10 years