Partners' Capital and Distributions (Tables)

12 Months Ended

Dec. 31, 2017

Partners' Capital Notes [Abstract]

Changes In Outstanding Limited Partner Units

The following table details the changes in the number of our limited partner units outstanding from January 1, 2015 through December 31, 2017:

Limited partner units outstanding on January 1, 2015	227,068,257
January 2015—Settlement of employee LTIP awards	354,529
During 2015—Other(a)	4,461
Limited partner units outstanding on December 31, 2015	227,427,247
February 2016—Settlement of employee LTIP awards	350,552
During 2016—Other(a)	6,117
Limited partner units outstanding on December 31, 2016	227,783,916
January 2017—Settlement of employee LTIP awards	216,679
During 2017—Other(a)	23,961
Limited partner units outstanding on December 31, 2017	228,024,556

(a) Limited partner units issued to settle the equity-based retainer paid to independent directors of our general partner.

Distributions Made to Limited Partner, by Distribution

Distributions we paid during 2015, 2016 and 2017 were as follows (in thousands, except per unit amount):

Payment Date	Per Unit Cash Distribution Amount		Total Cash Distribution
2/13/2015	$	0.6950	$	158,061
5/15/2015	0.7175		163,178
8/14/2015	0.7400		168,296
11/13/2015	0.7625		173,413
Total	$	2.9150	$	662,948
2/12/2016	$	0.7850	$	178,808
5/13/2016	0.8025		182,797
8/12/2016	0.8200		186,783
11/14/2016	0.8375		190,769
Total	$	3.2450	$	739,157
2/14/2017	$	0.8550	$	194,961
5/15/2017	0.8725		198,951
8/14/2017	0.8900		202,942
11/14/2017	0.9050		206,362
Total	$	3.5225	$	803,216