ACCOUNTING POLICIES (Details)	12 Months Ended
Dec. 31, 2015 level
Annual review for goodwill impairment
Number of levels below operating segments level considered for measuring reporting unit level	1
Employee Post-Retirement Benefits
Moving average period of basis used to determine expected return on plan assets	5 years
Corporate \| Minimum
Plant, property and equipment
Annual depreciation rate on straight-line basis	3.00%
Corporate \| Maximum
Plant, property and equipment
Annual depreciation rate on straight-line basis	20.00%
Natural Gas Pipelines \| Pipeline \| Minimum
Plant, property and equipment
Annual depreciation rate on straight-line basis	1.00%
Natural Gas Pipelines \| Pipeline \| Maximum
Plant, property and equipment
Annual depreciation rate on straight-line basis	6.00%
Natural Gas Pipelines \| Compression \| Minimum
Plant, property and equipment
Annual depreciation rate on straight-line basis	1.00%
Natural Gas Pipelines \| Compression \| Maximum
Plant, property and equipment
Annual depreciation rate on straight-line basis	6.00%
Liquids Pipelines \| Pipeline \| Minimum
Plant, property and equipment
Annual depreciation rate on straight-line basis	2.00%
Liquids Pipelines \| Pipeline \| Maximum
Plant, property and equipment
Annual depreciation rate on straight-line basis	2.50%
Liquids Pipelines \| Pumping equipment \| Minimum
Plant, property and equipment
Annual depreciation rate on straight-line basis	2.00%
Liquids Pipelines \| Pumping equipment \| Maximum
Plant, property and equipment
Annual depreciation rate on straight-line basis	2.50%
Energy \| Power generation and natural gas storage plant, equipment and structures \| Minimum
Plant, property and equipment
Annual depreciation rate on straight-line basis	2.00%
Energy \| Power generation and natural gas storage plant, equipment and structures \| Maximum
Plant, property and equipment
Annual depreciation rate on straight-line basis	20.00%

Represents the moving average period used to determine expected return on plan assets under the defined benefit plan.

No definition available.

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- Definition

Represents the annual rate at which long lived, physical assets used in the normal conduct of business and not intended for resale are depreciated.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Reporting Unit
-URI http://asc.fasb.org/extlink&oid=6523643

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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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