Impairment

9 Months Ended

Sep. 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 September 30, 2020, we recorded a total impairment charge of $44.0 million, which related to the full cost ceiling limitation impairment charge.

In the nine-month period ended September 30, 2020, we recorded a total impairment charge of $253.8 million, which included a full cost ceiling limitation impairment charge of $215.8 million, and an asset impairment charge of $38.0 million.

The ceiling limitation impairment charges recorded in the nine-month period ended September 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, second and third quarters of 2020. No impairment was recorded for the three and nine-month periods ended September 30, 2019.

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 September 30, 2020 were $43.40 per barrel of oil and $1.97 per Mcf of natural gas, before price differential adjustments. 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.

The asset impairment charge of $38.0 million recorded in the nine-month period ended September 30, 2020 resulted from writing down of the net carrying amount of the office headquarters building assets to their estimated fair value less estimated costs to sell the building. In May 2020, the Company entered into an agreement for the sale of its corporate headquarters building located in Oklahoma City, OK. The building sale closed on August 31, 2020.

In accordance with the applicable accounting guidance, FASB ASC 360-10-45-9, the Company reclassified its corporate headquarters building net carrying amount from Other property, plant and equipment, net, to Assets held for sale on the Condensed Consolidated Balance Sheets at June 30, 2020. The Company also reclassified the liabilities associated with the corporate headquarters building from Accounts payable and accrued expenses to Liabilities held for sale on the Condensed Consolidated Balance Sheets at June 30, 2020. Further, the Company recorded an impairment charge of $38.0 million in the three-month period ended June 30, 2020 to write down the net carrying amount of the office headquarters building assets to their estimated fair value less estimated costs to sell the building. No impairment charges were recorded for the corporate headquarters building assets in the three and nine-month periods ended September 30, 2019.

Prior to the sale of the corporate headquarters building, the carrying amount of the building was assessed for recoverability and impairment using undiscounted cash flow measures of the consolidated Company as prescribed under ASC 360-10-35, rather than fair value as prescribed under ASC 360-10-45-9.