Partners' Equity and Cash Distributions (Narrative) (Details)
|
12 Months Ended |
|
Dec. 31, 2015
$ / shares
|
|---|
| Distribution Made to Limited Partner [Line Items] |
|
| Subordination Period End Percentage |
150.00%
|
| First |
|
| Distribution Made to Limited Partner [Line Items] |
|
| Minimum Quarterly Distribution, Per Unit |
$ 0.192625
|
| Second |
|
| Distribution Made to Limited Partner [Line Items] |
|
| Minimum Quarterly Distribution, Per Unit |
0.209375
|
| Third |
|
| Distribution Made to Limited Partner [Line Items] |
|
| Minimum Quarterly Distribution, Per Unit |
0.251250
|
| Final |
|
| Distribution Made to Limited Partner [Line Items] |
|
| Minimum Quarterly Distribution, Per Unit |
$ 0.251250
|
| Common and Subordinated | Second |
|
| Distribution Made to Limited Partner [Line Items] |
|
| Pro Rata Percentage of Distribution in Excess of Minimum |
85.00%
|
| Common and Subordinated | Third |
|
| Distribution Made to Limited Partner [Line Items] |
|
| Pro Rata Percentage of Distribution in Excess of Minimum |
75.00%
|
| Common and Subordinated | Final |
|
| Distribution Made to Limited Partner [Line Items] |
|
| Pro Rata Percentage of Distribution in Excess of Minimum |
50.00%
|
| Columbia Energy Group | Second |
|
| Distribution Made to Limited Partner [Line Items] |
|
| Pro Rata Percentage of Distribution in Excess of Minimum |
15.00%
|
| Columbia Energy Group | Third |
|
| Distribution Made to Limited Partner [Line Items] |
|
| Pro Rata Percentage of Distribution in Excess of Minimum |
25.00%
|
| Columbia Energy Group | Final |
|
| Distribution Made to Limited Partner [Line Items] |
|
| Pro Rata Percentage of Distribution in Excess of Minimum |
50.00%
|