v2.4.0.8

Subsequent Events (Details) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended												12 Months Ended			0 Months Ended		12 Months Ended			0 Months Ended	12 Months Ended						0 Months Ended
	Nov. 14, 2013	Aug. 14, 2013	May 15, 2013	Feb. 14, 2013	Nov. 14, 2012	Aug. 14, 2012	May 15, 2012	Feb. 14, 2012	Nov. 14, 2011	Aug. 12, 2011	May 13, 2011	Feb. 14, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Feb. 14, 2014 Subsequent Event [Member]	Feb. 03, 2014 Subsequent Event [Member]	Dec. 31, 2013 Management [Member]	Dec. 31, 2012 Management [Member]	Dec. 31, 2011 Management [Member]	Feb. 03, 2014 Management [Member] Subsequent Event [Member]	Dec. 31, 2013 Director [Member]		Dec. 31, 2012 Director [Member]		Dec. 31, 2011 Director [Member]		Feb. 03, 2014 Director [Member] Subsequent Event [Member]
Subsequent Event [Line Items]
Units granted																	178,184	251,166				16,424		20,054		20,284
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period																	3 years
Partners' Capital Account, Units, Unit-based Compensation																	388,819	476,682	722,766	505,492	387,216	1,884	[1]	4,964	[1]	4,952	[1]	1,603
Cash distribution per limited partner unit	$ 0.55750	$ 0.53250	$ 0.50750	$ 0.50	$ 0.485	$ 0.47125	$ 0.42	$ 0.4075	$ 0.4	$ 0.3925	$ 0.385	$ 0.37875	$ 2.0975	$ 1.78375	$ 1.55625	$ 0.585
Total cash distributions	$ 126,374	$ 120,707	$ 115,040	$ 113,340	$ 109,707	$ 106,597	$ 95,004	$ 92,177	$ 90,189	$ 88,498	$ 86,807	$ 85,398	$ 475,461	$ 403,485	$ 350,892	$ 132,800
[1] Limited partner units issued to settle the equity-based retainer paid to independent directors of our general partner.

X

- Definition

The total amount of distributions to limited partners.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 272

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 5

-Subparagraph (SAB TOPIC 4.F)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

The amount of the distribution per unit of limited partner interest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770



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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 16

-Subparagraph a, b

-Article 6

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X

- Definition

The number of units issued due to unit-based compensation.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 272

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

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X

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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X

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Details

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