Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- Details

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Fair value of the amount outstanding under the credit facility.

+ 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)

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-Topic 825

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13476-108611

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

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 210.5-02.22)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-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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-Name Regulation S-X (SX)

-Number 210

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

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-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from parent as a source of financing that is recorded as additional paid in capital.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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- Details

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- Details

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- Details

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Debt (Senior Credit Facilities) (Details) (USD $)	12 Months Ended	0 Months Ended
Debt (Senior Credit Facilities) (Details) (USD $)	Dec. 31, 2014	Aug. 05, 2014	Dec. 31, 2013	Aug. 29, 2014
Debt Instrument [Line Items]
Long-term Debt	202,801,000us-gaap_LongTermDebt		$ 156,887,000us-gaap_LongTermDebt
Senior Notes \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Variable rate basis	LIBOR
Senior Notes \| Base Rate
Debt Instrument [Line Items]
Variable rate basis	Base Rate
Loans Payable \| Senior Notes
Debt Instrument [Line Items]
Long-term Debt	0		116,000,000
Loans Payable \| Revolving Credit Facility
Debt Instrument [Line Items]
Long-term Debt	110,000,000	40,000,000
Distribution		80,000,000
Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Aggregate maximum principal amount				365,000,000
Availability under facility	101,000,000
Weighted average interest rate (as a percent)	2.46%
Revolving Credit Facility \| Line of Credit \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate (as a percentage)	2.25%
Revolving Credit Facility \| Line of Credit \| Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate (as a percentage)	1.25%
Revolving Credit Facility \| Line of Credit \| Sublimit for Issuance of Letters of Credit
Debt Instrument [Line Items]
Aggregate maximum principal amount				20,000,000
Revolving Credit Facility \| Line of Credit \| Sublimit for the Issuance of Swing Loans
Debt Instrument [Line Items]
Aggregate maximum principal amount				20,000,000
Line of Credit \| Letter of Credit
Debt Instrument [Line Items]
Letters of credit	3,000,000
Line of Credit \| Letter of Credit \| Insurance Activities
Debt Instrument [Line Items]
Letters of credit	2,900,000
Line of Credit \| Letter of Credit \| Environmental and Other Matters
Debt Instrument [Line Items]
Letters of credit	100,000