Net Earnings per Common Unit (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Basic earnings per common unit:
Net earnings	$ 102.9	$ 166.8
Net earnings allocable to General Partner	41.5	73.0
Weighted average units outstanding	18.5	18.5
Net earnings per common Unit (in dollars per unit)	$ 3.26	$ 4.98
Dilutive TNCLP units outstanding	0	0
Class B Common Units
Basic earnings per common unit:
Net earnings allocated	1.0	1.6
Common Units
Basic earnings per common unit:
Net earnings allocated	$ 60.4	$ 92.2

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The portion of profit or loss for the period which is attributable to the parent.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.20)

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Aggregate amount of net income allocated to general partners.

+ 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 Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section F

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Aggregate amount of net income allocated to limited partners.

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Per unit of ownership amount after tax of income (loss) available to outstanding limited partnership (LP) unit-holder.

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Weighted average number of limited partnership units outstanding determined by relating the portion of time within a reporting period that general partnership units have been outstanding to the total time in that period.

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Weighted average number of limited partnership units outstanding determined by relating the portion of time within a reporting period that limited partnership units have been outstanding to the total time in that period. Used in the calculation of diluted net income or loss per limited partnership unit.

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