Net parent investment additions.

No definition available.

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- Definition

The change during the period, from the beginning balance of accumulated depreciation, depletion and amortization (relating to property, plant and equipment) to the ending balance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

+ Details

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

+ Details

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- Definition

Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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- 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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- Details

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Property, Plant and Equipment - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Aug. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property Plant And Equipment [Line Items]
Depreciation, amortization and accretion		$ 23.7	$ 21.6	$ 18.4
Pipeline and Equipment \| Shell Pipeline Company L P
Property Plant And Equipment [Line Items]
Increase in Pipeline and equipment	$ 51.9
Increase in Accumulated depreciation	51.5
Increase in Net Parent Investment	$ 0.4