Asset Impairments	12 Months Ended
Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Asset Impairments	5. Asset Impairments 2021 Impairment. During the first quarter of 2021, we identified indicators that the carrying amounts of certain of our assets may not be recoverable and evaluated three of our drilling rigs with indicators of impairment. Based on our assumptions and analysis at that time, we determined that the carrying value of one of these rigs, for which we had concerns regarding future opportunities, was impaired. We recorded asset impairments aggregating $197.0 million for the Predecessor period from January 1, 2021 through April 23, 2021. Pursuant to fresh start accounting, our long-lived assets, including our drilling rigs, were valued at their estimated fair value on the Effective Date based on assumptions and market factors that we believed to be accurate at that time. On the Effective Date, the remaining economic useful life of each individual rig was validated or revised, if so indicated. Subsequently, at the end of 2021, we reviewed the marketability, age and physical condition of certain of our rigs in conjunction with other factors specific to the geographic markets in which our rigs are capable of operating and determined that, based on circumstances that arose in the fourth quarter of 2021, which we believed to be other than temporary, the economic useful lives of certain of the rigs in our fleet were materially different than that determined at the Effective Date. At December 31, 2021, we identified three semisubmersible rigs for which we believed a change in the economic useful life was appropriate. In connection with this reassessment, we evaluated each rig for recoverability and determined that the carrying values of two of these rigs were impaired. We recorded an aggregate impairment loss of $132.4 million in the Successor period from April 24, 2021 through December 31, 2021 to write down the carrying value of these rigs to their estimated fair values. In addition, we reviewed one other rig with an indicator of impairment and determined that no impairment had occurred at December 31, 2021. We collectively refer to rigs impaired during the Successor period from April 24, 2021 through December 31, 2021 and the Predecessor period from January 1, 2021 through April 23, 2021 as the 2021 Impaired Rigs. We estimated the fair values of the 2021 Impaired Rigs using an income approach, whereby the fair value of the rig was estimated based on a calculation of each rig’s future net cash flows. These calculations utilized significant unobservable inputs, including management’s assumptions related to estimated dayrate revenue, rig utilization and, when applicable, estimated capital expenditures, repair and regulatory survey costs, as well as estimated proceeds that may be received on ultimate disposition of the rig. Our fair value estimate was representative of a Level 3 fair value measurement due to the significant level of estimation involved and the lack of transparency as to the inputs used. 2020 Impairments. During the first quarter of 2020, the business climate in which we operate experienced a significant adverse change that resulted in a dramatic decline in oil prices. During the first quarter of 2020, we evaluated five rigs with indicators of impairment. Based on our assumptions and analysis at that time, we determined that the carrying values of four of our drilling rigs were impaired and recorded an aggregate impairment charge of $774.0 million to write down the carrying values of these rigs to their estimated fair values. During the fourth quarter of 2020, we evaluated three drilling rigs with indicators of impairment, including one rig that was previously impaired in the first quarter of 2020. Based on further diminished business opportunities for the previously impaired rig, we reassessed our business plan and, after consideration of several factors, including the costs of relocating and stacking the rig, concluded that the carrying value of this rig was impaired at December 31, 2020. We recognized an additional impairment charge of $68.0 million to further adjust the carrying value of this rig to its fair value. We collectively refer to rigs impaired during the first and fourth quarters of 2020 as the 2020 Impaired Rigs. We estimated the fair values of the 2020 Impaired Rigs using an income approach, as described above. Our fair value estimates were representative of Level 3 fair value measurements due to the significant level of estimation involved and the lack of transparency as to the inputs used. See Note 1 "General Information — Impairment of Long-Lived Assets" and Note 9 "Financial Instruments and Fair Value Disclosures."

Asset Impairments

12 Months Ended

Dec. 31, 2022

Goodwill and Intangible Assets Disclosure [Abstract]

5. Asset Impairments

2021 Impairment. During the first quarter of 2021, we identified indicators that the carrying amounts of certain of our assets may not be recoverable and evaluated three of our drilling rigs with indicators of impairment. Based on our assumptions and analysis at that time, we determined that the carrying value of one of these rigs, for which we had concerns regarding future opportunities, was impaired. We recorded asset impairments aggregating $197.0 million for the Predecessor period from January 1, 2021 through April 23, 2021.

Pursuant to fresh start accounting, our long-lived assets, including our drilling rigs, were valued at their estimated fair value on the Effective Date based on assumptions and market factors that we believed to be accurate at that time. On the Effective Date, the remaining economic useful life of each individual rig was validated or revised, if so indicated. Subsequently, at the end of 2021, we reviewed the marketability, age and physical condition of certain of our rigs in conjunction with other factors specific to the geographic markets in which our rigs are capable of operating and determined that, based on circumstances that arose in the fourth quarter of 2021, which we believed to be other than temporary, the economic useful lives of certain of the rigs in our fleet were materially different than that determined at the Effective Date. At December 31, 2021, we identified three semisubmersible rigs for which we believed a change in the economic useful life was appropriate. In connection with this reassessment, we evaluated each rig for recoverability and determined that the carrying values of two of these rigs were impaired. We recorded an aggregate impairment loss of $132.4 million in the Successor period from April 24, 2021 through December 31, 2021 to write down the carrying value of these rigs to their estimated fair values. In addition, we reviewed one other rig with an indicator of impairment and determined that no impairment had occurred at December 31, 2021.

We collectively refer to rigs impaired during the Successor period from April 24, 2021 through December 31, 2021 and the Predecessor period from January 1, 2021 through April 23, 2021 as the 2021 Impaired Rigs. We estimated the fair values of the 2021 Impaired Rigs using an income approach, whereby the fair value of the rig was estimated based on a calculation of each rig’s future net cash flows. These calculations utilized significant unobservable inputs, including management’s assumptions related to estimated dayrate revenue, rig utilization and, when applicable, estimated capital expenditures, repair and regulatory survey costs, as well as estimated proceeds that may be received on ultimate disposition of the rig. Our fair value estimate was representative of a Level 3 fair value measurement due to the significant level of estimation involved and the lack of transparency as to the inputs used.

2020 Impairments. During the first quarter of 2020, the business climate in which we operate experienced a significant adverse change that resulted in a dramatic decline in oil prices. During the first quarter of 2020, we evaluated five rigs with indicators of impairment. Based on our assumptions and analysis at that time, we determined that the carrying values of four of our drilling rigs were impaired and recorded an aggregate impairment charge of $774.0 million to write down the carrying values of these rigs to their estimated fair values.

During the fourth quarter of 2020, we evaluated three drilling rigs with indicators of impairment, including one rig that was previously impaired in the first quarter of 2020. Based on further diminished business opportunities for the previously impaired rig, we reassessed our business plan and, after consideration of several factors, including the costs of relocating and stacking the rig, concluded that the carrying value of this rig was impaired at December 31, 2020. We recognized an additional impairment charge of $68.0 million to further adjust the carrying value of this rig to its fair value.

We collectively refer to rigs impaired during the first and fourth quarters of 2020 as the 2020 Impaired Rigs. We estimated the fair values of the 2020 Impaired Rigs using an income approach, as described above. Our fair value estimates were representative of Level 3 fair value measurements due to the significant level of estimation involved and the lack of transparency as to the inputs used.

See Note 1 "General Information — Impairment of Long-Lived Assets" and Note 9 "Financial Instruments and Fair Value Disclosures."