Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2018

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment Table

A summary of the historical cost of property, plant and equipment is as follows:

		December 31,
thousands	Estimated Useful Life	2018		2017
Land	n/a	$	4,653	$	4,450
Gathering systems and processing complexes	15 to 40 years	8,550,373		7,113,114
Pipelines and equipment	6 to 45 years	172,497		137,644
Assets under construction	n/a	490,705		579,501
Other	3 to 40 years	32,000		29,826
Total property, plant and equipment		9,250,228		7,864,535
Less accumulated depreciation		2,638,155		2,133,644
Net property, plant and equipment		$	6,612,073	$	5,730,891