Impairment

6 Months Ended

Jun. 30, 2020

Property, Plant and Equipment [Abstract]

Impairment

Impairment

The Company assesses the need to impair its oil and gas properties during its quarterly full cost pool ceiling limitation calculation. The Company analyzes various property, plant and equipment for impairment when certain triggering events occur by comparing the carrying values of the assets to their estimated fair values. The full cost pool ceiling limitation and estimated fair values of other assets were determined in accordance with the policies discussed in Note 1.

In the three-month period ended June 30, 2020, we recorded a total impairment charge of $201.8 million, which included a full cost ceiling limitation impairment charge of $163.8 million, and an impairment charge of $38.0 million to write down the value of the Company's office headquarters, classified as assets held for sale, to its estimated fair value less estimated costs to sell the building.

In the six-month period ended June 30, 2020, we recorded a total impairment charge of $209.8 million, which included a full cost ceiling limitation impairment charge of $171.8 million, and an impairment charge of $38.0 million to write down the value of the Company's office headquarters, classified as assets held for sale, to its estimated fair value less estimated costs to sell the building.

The ceiling limitation impairment charges recorded in the six-month period ended June 30, 2020 resulted from various factors, including a decrease in proved reserve value driven by a significant decline in the trailing twelve-month weighted average oil and natural gas prices in the first and second quarters of 2020. No impairment was recorded for the three and six-month period ended June 30, 2019. Impairment charges for the Company's office headquarters is further discussed in Note 6.

Calculation of the full cost ceiling test is based on, among other factors, average prices for the trailing twelve-month period determined by reference to the first-day-of-the-month index prices ("SEC prices") as adjusted for price differentials and other contractual arrangements. The SEC prices utilized in the calculation of proved reserves included in the full cost ceiling test at June 30, 2020 were $47.17 per barrel of oil and $2.07 per Mcf of natural gas, before price differential adjustments.