Net Income Per Limited Partner Unit
12 Months Ended
Dec. 31, 2015
Earnings Per Share [Abstract]  
Net Income Per Limited Partner Unit
Net Income Per Limited Partner Unit
The Partnership computes earnings per unit using the two-class method for Master Limited Partnerships. Under the two-class method, earnings per unit is calculated as if all of the earnings for the period were distributed under the terms of the Partnership Agreement, regardless of whether the general partner has discretion over the amount of distributions to be made in any particular period, whether those earnings would actually be distributed during a particular period from an economic or practical perspective or whether the general partner has other legal or contractual limitations on its ability to pay distributions that would prevent it from distributing all of the earnings for a particular period.
The Partnership calculates net income available to limited partners based on the distributions pertaining to the current period's net income. After adjusting for the appropriate period's distributions, the remaining undistributed earnings or excess distributions over earnings, if any, are allocated to the limited partners in accordance with the contractual terms of the Partnership Agreement and as further prescribed by ASC 260 under the two-class method.
The two-class method does not impact our overall net income or other financial results; however, in periods in which aggregate net income exceeds our aggregate distributions for such period, it will have the impact of reducing net income per limited partner unit. This result occurs as a larger portion of our aggregate earnings, as if distributed, is allocated to the incentive distribution rights holder under the terms of the Partnership Agreement, even though we make distributions on the basis of available cash and not earnings.
Net income per unit applicable to common units and to subordinated units is computed by dividing the respective limited partners’ interest in net income by the weighted-average number of common units and subordinated units outstanding for the period. The classes of participating securities include common units, subordinated units and incentive distribution rights. Basic and diluted net income per unit are the same because the Partnership does not have any potentially dilutive units outstanding for the periods presented.
Pursuant to our cash distribution policy, within 60 days after the end of each quarter, we intend to distribute to the holders of common units and subordinated units on a quarterly basis at least the minimum quarterly distribution of $0.1675 per unit, or $0.67 on an annualized basis, to the extent we have sufficient cash after establishment of cash reserves and payment of fees and expenses, including payments to our general partner and its affiliates.
On January 29, 2016, the board of directors of MLP GP, the Partnership's general partner, declared a quarterly cash distribution for the period October 1, 2015, through December 31, 2015, of $0.1800 per unit, or $18.1 million in total. This distribution is payable on February 19, 2016, to unit holders of record as of February 11, 2016.

The calculation of net income per unit is as follows:
 
 

Year Ended December 31, 2015                                                                           (in millions, except per unit data)
Limited Partners' Common Units
 
Limited Partners' Subordinated Units
 
Incentive Distribution Rights
 
Total
Net income attributable to partners
 
 
 
 
 
 
 
Distribution
$
32.9

 
$
28.7

 
$

 
$
61.6

Net income in excess of distribution(1)
6.7

 
5.1

 
0.6

 
12.4

Net income attributable to partners
$
39.6

 
$
33.8

 
$
0.6

 
$
74.0

 
 
 
 
 
 
 
 
Weighted-average limited partner units outstanding
 
 
 
 
 
 
 
Basic and diluted
53.8

 
46.8

 
 
 
100.6

Net income attributable to partners' ownership interest subsequent to IPO per limited partner unit
 
 
 
 
 
 
 
Basic and diluted
$
0.74

 
$
0.72

 
 
 
$
0.74

(1) Net income attributable to partners in excess of distribution is for the period subsequent to the IPO.