Property, Plant and Equipment

12 Months Ended

Dec. 31, 2014

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

8.  PROPERTY, PLANT AND EQUIPMENT

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

		December 31,
thousands	Estimated Useful Life	2014		2013
Land	n/a	$	2,839	$	2,584
Gathering systems	3 to 47 years	4,790,974		3,673,008
Pipelines and equipment	15 to 45 years	151,107		146,008
Assets under construction	n/a	464,507		405,633
Other	3 to 40 years	15,272		11,867
Total property, plant and equipment		5,424,699		4,239,100
Accumulated depreciation		1,040,328		855,845
Net property, plant and equipment		$	4,384,371	$	3,383,255

The cost of property classified as “Assets under construction” is excluded from capitalized costs being depreciated. These amounts represent property that is not yet suitable to be placed into productive service as of the respective balance sheet date.

At December 31, 2013, other long-term assets includes $4.6 million of unguaranteed residual value related to the capital lease component of a processing agreement assumed in connection with the acquisition of the Granger straddle plant as a part of the MGR acquisition in January 2012. This agreement, in which WES was the lessor, was replaced effective April 1, 2014, with a gas conditioning agreement that does not satisfy criteria required for lease classification. As such, during the second quarter of 2014, the $4.6 million capital lease asset was reclassified from other long-term assets to property, plant and equipment and commenced depreciation.

During 2014, WES recognized impairments of $3.1 million, primarily related to a non-operational plant in the Powder River Basin that was impaired to its estimated fair value of $2.4 million, using Level 3 fair-value inputs, the cancellation of various capital projects by the third-party operator of the Non-Operated Marcellus Interest systems and a compressor no longer in service at the Hilight system.

During 2013, WES recognized a $1.2 million impairment primarily related to the cancellation of various capital projects by the third-party operator of the Non-Operated Marcellus Interest systems.

During 2012, WES recognized a $6.0 million impairment related to a gathering system in central Wyoming that was impaired to its estimated fair value using Level 3 fair-value inputs and an impairment of $0.6 million for the original installation costs on a compressor relocated within WES’s operating assets.