Equity Method Investments (Tables)
 12 Months Ended
Dec. 31, 2015
Variable Interest Entities And Equity Investments [Abstract]  
Equity Method Investments Schedule of Ownership Percentage
The following is a list of the Partnership's equity method investments at December 31, 2015: 
Investee
Type of Investment
% of Voting Power or Interest Held
Hardy Storage Company, LLC
LLC Membership
49.0
%
Pennant Midstream, LLC
LLC Membership
47.5
%
Millennium Pipeline Company, L.L.C.
LLC Membership
47.5
%
Schedule Of Equity Method Investments
Year Ended December 31, (in millions)
2015
 
2014
 
2013
 
 
 
Predecessor
 
Predecessor
Millennium Pipeline
 
 
 
 
 
Statement of Income Data:
 
 
 
 
 
Net Revenues
$
206.3

 
$
190.5

 
$
157.8

Operating Income
136.1

 
128.8

 
101.3

Net Income
98.0

 
89.6

 
63.0

Balance Sheet Data:
 
 
 
 
 
Current Assets
35.7

 
32.1

 
38.3

Noncurrent Assets
987.1

 
1,016.3

 
1,033.8

Current Liabilities
44.4

 
42.6

 
58.8

Noncurrent Liabilities
535.8

 
568.3

 
599.7

Total Members’ Equity
442.6

 
437.5

 
413.6

Contribution/Distribution Data:(1)
 
 
 
 
 
Contributions to Millennium Pipeline
1.4

 
2.6

 
16.6

Distribution of earnings from Millennium Pipeline
47.5

 
35.6

 
29.0

Hardy Storage
 
 
 
 
 
Statement of Operations Data:
 
 
 
 
 
Net Revenues
$
23.4

 
$
23.6

 
$
24.4

Operating Income
15.3

 
16.1

 
16.5

Net Income
10.3

 
10.6

 
10.6

Balance Sheet Data:
 
 
 
 
 
Current Assets
12.1

 
12.0

 
12.5

Noncurrent Assets
155.5

 
157.4

 
160.2

Current Liabilities
19.3

 
17.1

 
18.3

Noncurrent Liabilities
68.5

 
77.4

 
85.7

Total Members’ Equity
79.8

 
74.9

 
68.7

Contribution/Distribution Data:(1)
 
 
 
 
 
Contributions to Hardy Storage
—

 
—

 
—

Distribution of earnings from Hardy Storage
2.6

 
2.2

 
3.1

Pennant
 
 
 
 
 
Statement of Operations Data:
 
 
 
 
 
Net Revenues
$
34.6

 
$
8.5

 
$
2.0

Operating Income (Loss)
17.8

 
(2.4
)
 
1.3

Net Income (Loss)
17.8

 
(2.4
)
 
1.3

Balance Sheet Data:
 
 
 
 
 
Current Assets
11.0

 
23.7

 
34.1

Noncurrent Assets
389.6

 
380.0

 
231.9

Current Liabilities
8.4

 
8.6

 
11.4

Total Members’ Equity
392.2

 
395.1

 
254.6

Contribution/Distribution Data:(1)
 
 
 
 
 
Contributions to Pennant
—

 
66.6

 
108.9

Distribution of earnings from Pennant
7.1

 
—

 
—

Return of capital from Pennant
16.0

 
—

 
—


(1)Contribution and distribution data represents the Partnership's portion based on the Partnership's ownership percentage of each investment.