Impairment of long-lived assets

6 Months Ended

Jun. 30, 2016

Asset Impairment Charges [Abstract]

Impairment of long-lived assets

Impairment of long-lived assets

During the second quarter of 2015, the Company recognized an impairment of coalbed natural gas gathering assets at the pipeline and midstream segment of $3.0 million, which is recorded in operation and maintenance expense on the Consolidated Statements of Income. The impairment is related to coalbed natural gas gathering assets located in Wyoming where there had been continued decline in natural gas development and production activity due to low natural gas prices. The coalbed natural gas gathering assets were written down to their estimated fair value that was determined using the income approach.

For more information on this nonrecurring fair value measurement, see Note 13.

For information regarding impairments related to the Company's discontinued operations, see Note 10.