Long-Term Incentive Plan

3 Months Ended

Mar. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Long-Term Incentive Plan

Long-Term Incentive Plan

The compensation committee of our general partner’s board of directors administers our long-term incentive plan (“LTIP”) covering certain of our employees and the independent directors of our general partner. The LTIP primarily consists of phantom units and permits the grant of awards covering an aggregate payout of 11.9 million of our limited partner units. The estimated units remaining available under the LTIP at March 31, 2018 total 2.1 million.

Our equity-based incentive compensation expense was as follows (in thousands):

	Three Months Ended March 31,
	2017		2018
Performance-based awards	$	3,481	$	5,924
Time-based awards	666		708
Total	$	4,147	$	6,632
Allocation of LTIP expense on our consolidated statements of income:
G&A expense	$	4,118	$	6,577
Operating expense	29		55
Total	$	4,147	$	6,632

On February 1, 2018, 294,054 unit awards were issued pursuant to our LTIP. These grants included both performance-based and time-based awards and have a three-year vesting period that will end on December 31, 2020.

Basic and Diluted Net Income Per Limited Partner Unit

The difference between our actual limited partner units outstanding and our weighted-average number of limited partner units outstanding used to calculate basic net income per unit is due to the impact of: (i) the unit awards issued to non-employee directors and (ii) the weighted average effect of units actually issued during a period.  The difference between the weighted-average number of limited partner units outstanding used for basic and diluted net income per unit calculations on our consolidated statements of income is primarily the dilutive effect of unit awards associated with our LTIP that have not yet vested.